diff --git a/CHANGES b/CHANGES
index 6dc610ed0..ef1812da8 100644
--- a/CHANGES
+++ b/CHANGES
@@ -928,7 +928,7 @@ Wed.	April 25, 2007. ken@xelerance.com.  Summary for 3.9.6 tcpdump release
 	 RFC 4340.
 	Add support for per-VLAN spanning tree and per-VLAN rapid spanning tree
 	Add support for Multiple-STP as per 802.1s
-	Add support for the cisco propriatry 'dynamic trunking protocol'
+	Add support for the cisco proprietary 'dynamic trunking protocol'
 	Add support for the cisco proprietary VTP protocol
 	Update dhcp6 options table as per IETF standardization activities
 
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 996966b28..d340dbd66 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1011,7 +1011,7 @@ if(EXISTS ${CMAKE_SOURCE_DIR}/.devel OR EXISTS ${CMAKE_BINARY_DIR}/.devel)
         # __declspec(align), because the only structures whose layout
         # we precisely specify are those that get overlaid on packet
         # data, and in those every element is an array of octets so
-        # that we have full control over the size and aligmnet, and,
+        # that we have full control over the size and alignment, and,
         # apparently, jmp_buf has such a declaration on x86, meaning
         # that everything that includes netdissect.h, i.e. almost every
         # file in tcpdump, gets a warning.
diff --git a/addrtoname.c b/addrtoname.c
index d3c352f59..f2a13a330 100644
--- a/addrtoname.c
+++ b/addrtoname.c
@@ -1115,7 +1115,7 @@ static const struct ipxsap_ent {
 	{ 0x030a, "GalacticommWorldgroupServer" },
 	{ 0x030c, "IntelNetport2/HP JetDirect/HP Quicksilver" },
 	{ 0x0320, "AttachmateGateway" },
-	{ 0x0327, "MicrosoftDiagnostiocs" },
+	{ 0x0327, "MicrosoftDiagnostics" },
 	{ 0x0328, "WATCOM SQL Server" },
 	{ 0x0335, "MultiTechSystems MultisynchCommServer" },
 	{ 0x0343, "Xylogics RemoteAccessServer/LANModem" },
diff --git a/extract.h b/extract.h
index d7d803dfb..c1b486d37 100644
--- a/extract.h
+++ b/extract.h
@@ -261,7 +261,7 @@ EXTRACT_IPV4_TO_HOST_ORDER(const void *p)
  * quantities the hard way - fetch the bytes one at a time and
  * assemble them.
  *
- * XXX - ARM is a special case.  ARMv1 through ARMv5 didn't suppory
+ * XXX - ARM is a special case.  ARMv1 through ARMv5 didn't support
  * unaligned loads; ARMv6 and later support it *but* have a bit in
  * the system control register that the OS can set and that causes
  * unaligned loads to fault rather than succeeding.
diff --git a/ftmacros.h b/ftmacros.h
index 7975463b3..ba95c4aac 100644
--- a/ftmacros.h
+++ b/ftmacros.h
@@ -64,7 +64,7 @@
   /*
    * We need this to get the versions of socket functions that
    * use socklen_t.  Define it only if it's not already defined,
-   * so we don't get redefiniton warnings.
+   * so we don't get redefinition warnings.
    */
   #ifndef _XOPEN_SOURCE_EXTENDED
     #define _XOPEN_SOURCE_EXTENDED
diff --git a/makemib b/makemib
index 97e78754f..f734bb733 100755
--- a/makemib
+++ b/makemib
@@ -36,7 +36,7 @@
 #
 # This script needs to be run by "gawk" (GNU awk).  "nawk" will work, but
 # dump will get a recursion error if you process LARGE mibs.  While it would
-# by farily easy to rewrite this not to use recursion (and also easy to
+# by fairly easy to rewrite this not to use recursion (and also easy to
 # eliminate use of gsub and functions to use classic "awk"), you have to
 # order the structure declarations in defined-first order for the compiler
 # not to barf; too bad tsort doesn't take arguments.
diff --git a/mib.h b/mib.h
index 6c8e63c97..4f83e6b89 100644
--- a/mib.h
+++ b/mib.h
@@ -765,13 +765,13 @@ _icmpInParmProbs_obj = {
 	"icmpInParmProbs", 5, 0,
 	NULL, &_icmpInTimeExcds_obj
 },
-_icmpInSrcQuenchs_obj = {
-	"icmpInSrcQuenchs", 6, 0,
+_icmpInSrcQuenches_obj = {
+	"icmpInSrcQuenches", 6, 0,
 	NULL, &_icmpInParmProbs_obj
 },
 _icmpInRedirects_obj = {
 	"icmpInRedirects", 7, 0,
-	NULL, &_icmpInSrcQuenchs_obj
+	NULL, &_icmpInSrcQuenches_obj
 },
 _icmpInEchos_obj = {
 	"icmpInEchos", 8, 0,
@@ -817,13 +817,13 @@ _icmpOutParmProbs_obj = {
 	"icmpOutParmProbs", 18, 0,
 	NULL, &_icmpOutTimeExcds_obj
 },
-_icmpOutSrcQuenchs_obj = {
-	"icmpOutSrcQuenchs", 19, 0,
+_icmpOutSrcQuenches_obj = {
+	"icmpOutSrcQuenches", 19, 0,
 	NULL, &_icmpOutParmProbs_obj
 },
 _icmpOutRedirects_obj = {
 	"icmpOutRedirects", 20, 0,
-	NULL, &_icmpOutSrcQuenchs_obj
+	NULL, &_icmpOutSrcQuenches_obj
 },
 _icmpOutEchos_obj = {
 	"icmpOutEchos", 21, 0,
diff --git a/nameser.h b/nameser.h
index 75e672b14..08b680e01 100644
--- a/nameser.h
+++ b/nameser.h
@@ -87,7 +87,7 @@
 #define UPDATEMA	0xd		/* modify all named resource record */
 
 #define ZONEINIT	0xe		/* initial zone transfer */
-#define ZONEREF		0xf		/* incremental zone referesh */
+#define ZONEREF		0xf		/* incremental zone refresh */
 
 /*
  * Undefine various #defines from various System V-flavored OSes (Solaris,
@@ -112,7 +112,7 @@
 #define NOERROR		0		/* no error */
 #define FORMERR		1		/* format error */
 #define SERVFAIL	2		/* server failure */
-#define NXDOMAIN	3		/* non existent domain */
+#define NXDOMAIN	3		/* nonexistent domain */
 #define NOTIMP		4		/* not implemented */
 #define REFUSED		5		/* query refused */
 	/* non standard */
@@ -125,7 +125,7 @@
 #define T_NS		2		/* authoritative server */
 #define T_MD		3		/* mail destination */
 #define T_MF		4		/* mail forwarder */
-#define T_CNAME		5		/* connonical name */
+#define T_CNAME		5		/* canonical name */
 #define T_SOA		6		/* start of authority zone */
 #define T_MB		7		/* mailbox domain name */
 #define T_MG		8		/* mail group member */
diff --git a/print-802_11.c b/print-802_11.c
index 28d4d6f1f..50abc6c0f 100644
--- a/print-802_11.c
+++ b/print-802_11.c
@@ -67,7 +67,7 @@
 #define	IEEE802_11_STATUS_LEN		2
 #define	IEEE802_11_REASON_LEN		2
 
-/* Length of previous AP in reassocation frame */
+/* Length of previous AP in reassociation frame */
 #define	IEEE802_11_AP_LEN		6
 
 #define	T_MGMT 0x0  /* management */
@@ -1744,7 +1744,7 @@ handle_action(netdissect_options *ndo,
 	case 7: ND_PRINT("HT "); PRINT_HT_ACTION(GET_U_1(p + 1)); break;
 	case 13: ND_PRINT("MeshAction "); PRINT_MESH_ACTION(GET_U_1(p + 1)); break;
 	case 14:
-		ND_PRINT("MultiohopAction ");
+		ND_PRINT("MultihopAction");
 		PRINT_MULTIHOP_ACTION(GET_U_1(p + 1)); break;
 	case 15:
 		ND_PRINT("SelfprotectAction ");
diff --git a/print-802_15_4.c b/print-802_15_4.c
index fd75b1595..8853d44f5 100644
--- a/print-802_15_4.c
+++ b/print-802_15_4.c
@@ -250,7 +250,7 @@ static const char *p_mlme_short_names[] = {
 	"TVWS PHY Operating Mode Description IE",	/* 0x2b */
 	"TVWS Device Capabilities IE",			/* 0x2c */
 	"TVWS Device Category IE",			/* 0x2d */
-	"TVWS Device Identiication IE",			/* 0x2e */
+	"TVWS Device Identification IE",		/* 0x2e */
 	"TVWS Device Location IE",			/* 0x2f */
 	"TVWS Channel Information Query IE",		/* 0x30 */
 	"TVWS Channel Information Source IE",		/* 0x31 */
@@ -418,7 +418,7 @@ static const char *mac_c_names[] = {
 #define FC_ADDRESSING_MODE_LONG         0x03
 
 /*
- * IEEE 802.15.4 CRC 16 function. This is using CCITT polynomical of 0x1021,
+ * IEEE 802.15.4 CRC 16 function. This is using the CCITT polynomial of 0x1021,
  * but the initial value is 0, and the bits are reversed for both in and out.
  * See section 7.2.10 of 802.15.4-2015 for more information.
  */
@@ -470,7 +470,7 @@ ieee802_15_4_reverse32(uint32_t x)
 }
 
 /*
- * IEEE 802.15.4 CRC 32 function. This is using ANSI X3.66-1979 polynomical of
+ * IEEE 802.15.4 CRC 32 function. This is using the ANSI X3.66-1979 polynomial of
  * 0x04C11DB7, but the initial value is 0, and the bits are reversed for both
  * in and out. See section 7.2.10 of 802.15.4-2015 for more information.
  */
@@ -1303,7 +1303,7 @@ ieee802_15_4_print_mlme_ie_list(netdissect_options *ndo,
 }
 
 /*
- * Multiplexd IE (802.15.9) parsing and printing.
+ * Multiplexed IE (802.15.9) parsing and printing.
  *
  * Returns number of bytes consumed from packet or -1 in case of error.
  */
@@ -1664,7 +1664,7 @@ ieee802_15_4_print_command_data(netdissect_options *ndo,
 			return caplen;
 		}
 		break;
-	case 0x03: /* Diassociation Notification command */
+	case 0x03: /* Disassociation Notification command */
 		if (caplen != 1) {
 			ND_PRINT("Invalid Disassociation Notification command length");
 			return -1;
@@ -2038,19 +2038,19 @@ ieee802_15_4_std_frames(netdissect_options *ndo,
 	}
 
 	switch (security_level) {
-	case 0: /*FALLTHOUGH */
+	case 0: /*FALLTHROUGH */
 	case 4:
 		miclen = 0;
 		break;
-	case 1: /*FALLTHOUGH */
+	case 1: /*FALLTHROUGH */
 	case 5:
 		miclen = 4;
 		break;
-	case 2: /*FALLTHOUGH */
+	case 2: /*FALLTHROUGH */
 	case 6:
 		miclen = 8;
 		break;
-	case 3: /*FALLTHOUGH */
+	case 3: /*FALLTHROUGH */
 	case 7:
 		miclen = 16;
 		break;
@@ -2360,19 +2360,19 @@ ieee802_15_4_mp_frame(netdissect_options *ndo,
 	}
 
 	switch (security_level) {
-	case 0: /*FALLTHOUGH */
+	case 0: /*FALLTHROUGH */
 	case 4:
 		miclen = 0;
 		break;
-	case 1: /*FALLTHOUGH */
+	case 1: /*FALLTHROUGH */
 	case 5:
 		miclen = 4;
 		break;
-	case 2: /*FALLTHOUGH */
+	case 2: /*FALLTHROUGH */
 	case 6:
 		miclen = 8;
 		break;
-	case 3: /*FALLTHOUGH */
+	case 3: /*FALLTHROUGH */
 	case 7:
 		miclen = 16;
 		break;
diff --git a/print-atm.c b/print-atm.c
index 904fc4792..51c53b0fb 100644
--- a/print-atm.c
+++ b/print-atm.c
@@ -106,7 +106,7 @@
 #define B_BEARER		0x5e	/* broadband bearer capability */
 #define B_LOWER			0x5f	/* broadband lower information */
 #define CALLING_PARTY		0x6c	/* calling party number */
-#define CALLED_PARTY		0x70	/* called party nmber */
+#define CALLED_PARTY		0x70	/* called party number */
 
 #define Q2931			0x09
 
diff --git a/print-bgp.c b/print-bgp.c
index 113af14e5..dfb6f0154 100644
--- a/print-bgp.c
+++ b/print-bgp.c
@@ -1598,7 +1598,7 @@ check_add_path(netdissect_options *ndo, const u_char *pptr, u_int length,
     }
 
     /*
-     * Scan through the NLRI information under the assumpetion that
+     * Scan through the NLRI information under the assumption that
      * it doesn't have path IDs.
      */
     for (offset = 0; offset < length;) {
diff --git a/print-ether.c b/print-ether.c
index 504d51c53..3a62771bf 100644
--- a/print-ether.c
+++ b/print-ether.c
@@ -412,7 +412,7 @@ ether_common_print(netdissect_options *ndo, const u_char *p, u_int length,
 }
 
 /*
- * Print an Ethernet frame while specyfing a non-standard Ethernet header
+ * Print an Ethernet frame while specifying a non-standard Ethernet header
  * length.
  * This might be encapsulated within another frame; we might be passed
  * a pointer to a function that can print header information for that
diff --git a/print-icmp6.c b/print-icmp6.c
index 75bcc8b01..f2937e49b 100644
--- a/print-icmp6.c
+++ b/print-icmp6.c
@@ -526,7 +526,7 @@ struct nd_rpl_security {
 #endif
 };
 
-/* section 6.2.1, DODAG Information Solication (DIS_IS) */
+/* section 6.2.1, DODAG Information Solicitation (DIS_IS) */
 struct nd_rpl_dis_is {
     nd_uint8_t rpl_dis_flags;
     nd_uint8_t rpl_dis_reserved;
diff --git a/print-isoclns.c b/print-isoclns.c
index df1179720..cb06e19a0 100644
--- a/print-isoclns.c
+++ b/print-isoclns.c
@@ -207,7 +207,7 @@ static const struct tok esis_option_values[] = {
     { ESIS_OPTION_SECURITY,        "Security" },
     { ESIS_OPTION_ES_CONF_TIME,    "ES Configuration Time" },
     { ESIS_OPTION_PRIORITY,        "Priority" },
-    { ESIS_OPTION_ADDRESS_MASK,    "Addressk Mask" },
+    { ESIS_OPTION_ADDRESS_MASK,    "Address Mask" },
     { ESIS_OPTION_SNPA_MASK,       "SNPA Mask" },
     { 0, NULL }
 };
@@ -612,7 +612,7 @@ static const struct tok isis_lsp_istype_values[] = {
 #define ISIS_PTP_ADJ_INIT 1
 #define ISIS_PTP_ADJ_DOWN 2
 
-static const struct tok isis_ptp_adjancey_values[] = {
+static const struct tok isis_ptp_adjacency_values[] = {
     { ISIS_PTP_ADJ_UP,    "Up" },
     { ISIS_PTP_ADJ_INIT,  "Initializing" },
     { ISIS_PTP_ADJ_DOWN,  "Down" },
@@ -3148,7 +3148,7 @@ isis_print(netdissect_options *ndo,
 	    tlv_ptp_adj = (const struct isis_tlv_ptp_adj *)tptr;
 	    if(tlen>=1) {
 		ND_PRINT("\n\t      Adjacency State: %s (%u)",
-		       tok2str(isis_ptp_adjancey_values, "unknown", GET_U_1(tptr)),
+		       tok2str(isis_ptp_adjacency_values, "unknown", GET_U_1(tptr)),
 		       GET_U_1(tptr));
 		tlen--;
 	    }
diff --git a/print-lisp.c b/print-lisp.c
index 756fff0ff..fc2006f4c 100644
--- a/print-lisp.c
+++ b/print-lisp.c
@@ -129,12 +129,12 @@ enum {
 };
 
 static const struct tok lisp_type [] = {
-	{ 0, "LISP-Reserved"			},
-	{ 1, "LISP-Map-Request"			},
-	{ 2, "LISP-Map-Reply"			},
-	{ 3, "LISP-Map-Register"		},
-	{ 4, "LISP-Map-Notify"			},
-	{ 8, "LISP-Encapsulated-Contol-Message" },
+	{ 0, "LISP-Reserved"			 },
+	{ 1, "LISP-Map-Request"			 },
+	{ 2, "LISP-Map-Reply"			 },
+	{ 3, "LISP-Map-Register"		 },
+	{ 4, "LISP-Map-Notify"			 },
+	{ 8, "LISP-Encapsulated-Control-Message" },
 	{ 0, NULL }
 };
 
diff --git a/print-ppp.c b/print-ppp.c
index 385053551..0a8e2c287 100644
--- a/print-ppp.c
+++ b/print-ppp.c
@@ -194,7 +194,7 @@ static const char *lcpconfopts[] = {
 	"deprecated(12)",	/* used to be a Multi-Link-Procedure*/
 	"Call-Back",		/* (13) */
 	"deprecated(14)",	/* used to be a Connect-Time */
-	"deprecated(15)",	/* used to be a Compund-Frames */
+	"deprecated(15)",	/* used to be a Compound-Frames */
 	"deprecated(16)",	/* used to be a Nominal-Data-Encap */
 	"MRRU",			/* (17) */
 	"12-Bit seq #",		/* (18) */
@@ -859,7 +859,7 @@ handle_chap(netdissect_options *ndo,
 	 * don't know which flavor of CHAP (i.e. CHAP-MD5, MS-CHAPv1,
 	 * MS-CHAPv2) is used at this point, we can't decode packet
 	 * specifically to each algorithms. Instead, we simply decode
-	 * the GCD (Gratest Common Denominator) for all algorithms.
+	 * the GCD (Greatest Common Denominator) for all algorithms.
 	 */
 	switch (code) {
 	case CHAP_CHAL:
diff --git a/print-radius.c b/print-radius.c
index 39dd2b860..e26ba567f 100644
--- a/print-radius.c
+++ b/print-radius.c
@@ -112,38 +112,38 @@
 
 /* Radius packet codes */
 /* https://www.iana.org/assignments/radius-types/radius-types.xhtml#radius-types-27 */
-#define RADCMD_ACCESS_REQ   1 /* Access-Request      */
-#define RADCMD_ACCESS_ACC   2 /* Access-Accept       */
-#define RADCMD_ACCESS_REJ   3 /* Access-Reject       */
-#define RADCMD_ACCOUN_REQ   4 /* Accounting-Request  */
-#define RADCMD_ACCOUN_RES   5 /* Accounting-Response */
-#define RADCMD_ACCESS_CHA  11 /* Access-Challenge    */
-#define RADCMD_STATUS_SER  12 /* Status-Server       */
-#define RADCMD_STATUS_CLI  13 /* Status-Client       */
-#define RADCMD_DISCON_REQ  40 /* Disconnect-Request  */
-#define RADCMD_DISCON_ACK  41 /* Disconnect-ACK      */
-#define RADCMD_DISCON_NAK  42 /* Disconnect-NAK      */
-#define RADCMD_COA_REQ     43 /* CoA-Request         */
-#define RADCMD_COA_ACK     44 /* CoA-ACK             */
-#define RADCMD_COA_NAK     45 /* CoA-NAK             */
-#define RADCMD_RESERVED   255 /* Reserved            */
+#define RADCMD_ACCESS_REQ    1 /* Access-Request      */
+#define RADCMD_ACCESS_ACC    2 /* Access-Accept       */
+#define RADCMD_ACCESS_REJ    3 /* Access-Reject       */
+#define RADCMD_ACCOUNT_REQ   4 /* Accounting-Request  */
+#define RADCMD_ACCOUNT_RES   5 /* Accounting-Response */
+#define RADCMD_ACCESS_CHA   11 /* Access-Challenge    */
+#define RADCMD_STATUS_SER   12 /* Status-Server       */
+#define RADCMD_STATUS_CLI   13 /* Status-Client       */
+#define RADCMD_DISCON_REQ   40 /* Disconnect-Request  */
+#define RADCMD_DISCON_ACK   41 /* Disconnect-ACK      */
+#define RADCMD_DISCON_NAK   42 /* Disconnect-NAK      */
+#define RADCMD_COA_REQ      43 /* CoA-Request         */
+#define RADCMD_COA_ACK      44 /* CoA-ACK             */
+#define RADCMD_COA_NAK      45 /* CoA-NAK             */
+#define RADCMD_RESERVED    255 /* Reserved            */
 
 static const struct tok radius_command_values[] = {
-    { RADCMD_ACCESS_REQ, "Access-Request" },
-    { RADCMD_ACCESS_ACC, "Access-Accept" },
-    { RADCMD_ACCESS_REJ, "Access-Reject" },
-    { RADCMD_ACCOUN_REQ, "Accounting-Request" },
-    { RADCMD_ACCOUN_RES, "Accounting-Response" },
-    { RADCMD_ACCESS_CHA, "Access-Challenge" },
-    { RADCMD_STATUS_SER, "Status-Server" },
-    { RADCMD_STATUS_CLI, "Status-Client" },
-    { RADCMD_DISCON_REQ, "Disconnect-Request" },
-    { RADCMD_DISCON_ACK, "Disconnect-ACK" },
-    { RADCMD_DISCON_NAK, "Disconnect-NAK" },
-    { RADCMD_COA_REQ,    "CoA-Request" },
-    { RADCMD_COA_ACK,    "CoA-ACK" },
-    { RADCMD_COA_NAK,    "CoA-NAK" },
-    { RADCMD_RESERVED,   "Reserved" },
+    { RADCMD_ACCESS_REQ,  "Access-Request" },
+    { RADCMD_ACCESS_ACC,  "Access-Accept" },
+    { RADCMD_ACCESS_REJ,  "Access-Reject" },
+    { RADCMD_ACCOUNT_REQ, "Accounting-Request" },
+    { RADCMD_ACCOUNT_RES, "Accounting-Response" },
+    { RADCMD_ACCESS_CHA,  "Access-Challenge" },
+    { RADCMD_STATUS_SER,  "Status-Server" },
+    { RADCMD_STATUS_CLI,  "Status-Client" },
+    { RADCMD_DISCON_REQ,  "Disconnect-Request" },
+    { RADCMD_DISCON_ACK,  "Disconnect-ACK" },
+    { RADCMD_DISCON_NAK,  "Disconnect-NAK" },
+    { RADCMD_COA_REQ,     "CoA-Request" },
+    { RADCMD_COA_ACK,     "CoA-ACK" },
+    { RADCMD_COA_NAK,     "CoA-NAK" },
+    { RADCMD_RESERVED,    "Reserved" },
     { 0, NULL}
 };
 
diff --git a/print-sctp.c b/print-sctp.c
index e000ed7d4..7d1f51be0 100644
--- a/print-sctp.c
+++ b/print-sctp.c
@@ -293,7 +293,7 @@ struct sctpUnifiedAbortHeavy{
 };
 
 /* For the graceful shutdown we must carry
- * the tag (in common header)  and the highest consequitive acking value
+ * the tag (in common header)  and the highest consecutive acking value
  */
 struct sctpShutdown {
   nd_uint32_t TSN_Seen;
diff --git a/print-sflow.c b/print-sflow.c
index 895d2546c..1d6e79ddd 100644
--- a/print-sflow.c
+++ b/print-sflow.c
@@ -690,7 +690,7 @@ sflow_print_flow_records(netdissect_options *ndo,
 
 	sflow_flow_record = (const struct sflow_flow_record_t *)tptr;
 
-	/* so, the funky encoding means we cannot blythly mask-off
+	/* so, the funky encoding means we cannot blithely mask-off
 	   bits, we must also check the enterprise. */
 
 	enterprise = GET_BE_U_4(sflow_flow_record->format);
diff --git a/print-snmp.c b/print-snmp.c
index d05a5d383..7301e3453 100644
--- a/print-snmp.c
+++ b/print-snmp.c
@@ -1090,7 +1090,7 @@ smi_print_value(netdissect_options *ndo,
 	}
 
 	if (NOTIFY_CLASS(pduid) && smiNode->access < SMI_ACCESS_NOTIFY) {
-	    ND_PRINT("[notNotifyable]");
+	    ND_PRINT("[notNotifiable]");
 	}
 
 	if (READ_CLASS(pduid) && smiNode->access < SMI_ACCESS_READ_ONLY) {
diff --git a/print-telnet.c b/print-telnet.c
index ea7464f0d..1dc6f1c5d 100644
--- a/print-telnet.c
+++ b/print-telnet.c
@@ -117,7 +117,7 @@ static const char *telcmds[] = {
 #define TELOPT_NAOVTS	14	/* negotiate about vertical tab stops */
 #define TELOPT_NAOVTD	15	/* negotiate about vertical tab disposition */
 #define TELOPT_NAOLFD	16	/* negotiate about output LF disposition */
-#define TELOPT_XASCII	17	/* extended ascic character set */
+#define TELOPT_XASCII	17	/* extended ascii character set */
 #define	TELOPT_LOGOUT	18	/* force logout */
 #define	TELOPT_BM	19	/* byte macro */
 #define	TELOPT_DET	20	/* data entry terminal */
diff --git a/tcpdump.1.in b/tcpdump.1.in
index 9c720d04a..79be03448 100644
--- a/tcpdump.1.in
+++ b/tcpdump.1.in
@@ -407,7 +407,7 @@ which should include a time format as defined by
 .BR strftime (3).
 If no time format is specified, each new file will overwrite the previous.
 Whenever a generated filename is not unique, tcpdump will overwrite the
-pre-existing data; providing a time specification that is coarser than the
+preexisting data; providing a time specification that is coarser than the
 capture period is therefore not advised.
 .IP
 If used in conjunction with the
@@ -1680,7 +1680,7 @@ The op (Query) and response code
 (NoError) were omitted, as was the class (C_IN) of the A record.
 .LP
 In the second example, \fIhelios\fP responds to query 2 with a
-response code of non-existent domain (NXDomain) with no answers,
+response code of nonexistent domain (NXDomain) with no answers,
 one name server and no authority records.
 The `*' indicates that
 the \fIauthoritative answer\fP bit was set.
diff --git a/tcpdump.c b/tcpdump.c
index 7cdbd8af4..e8c6b8162 100644
--- a/tcpdump.c
+++ b/tcpdump.c
@@ -808,7 +808,7 @@ droproot(const char *username, const char *chroot_dir)
 	} else
 		error("Couldn't find user '%.32s'", username);
 #ifdef HAVE_LIBCAP_NG
-	/* We don't need CAP_SETUID, CAP_SETGID and CAP_SYS_CHROOT any more. */
+	/* We don't need CAP_SETUID, CAP_SETGID and CAP_SYS_CHROOT anymore. */
 DIAG_OFF_ASSIGN_ENUM
 	capng_updatev(
 		CAPNG_DROP,
@@ -979,7 +979,7 @@ tstamp_precision_to_string(int precision)
  * along the lines of ioctl(), the fact that ioctl() operations are
  * largely specific to particular character devices but fcntl() operations
  * are either generic to all descriptors or generic to all descriptors for
- * regular files nonwithstanding.
+ * regular files notwithstanding.
  *
  * The Capsicum people decided that fine-grained control of descriptor
  * operations was required, so that you need to grant permission for