diff --git a/data/en/4.0.dict b/data/en/4.0.dict
index 33e4d2b748..4fe6115dad 100644
--- a/data/en/4.0.dict
+++ b/data/en/4.0.dict
@@ -13289,6 +13289,7 @@ RIGHT-WALL: RW- or ({@Xca-} & [[Xc-]]);
 <post-quote>:
   QUc- & {<wo-wall> or <wi-wall> or CP+};
 
+% underbar used like a quote-mark, e.g. for _bold text_
 « 《 【 『 「 „ “ ''.x ’’.x :
   QUd-;
 » 》 】 』 」 ” ''.y ’’.y :
@@ -13299,7 +13300,8 @@ RIGHT-WALL: RW- or ({@Xca-} & [[Xc-]]);
 
 % [[ZZZ-]]: link to "random" quotation marks that show up "for no reason".
 % Cannot use a blanket W+ here to pick up all W connectors, because ... ??
-""": QUd- or <post-quote> or [[ZZZ-]];
+% Underbar is for _bold text_.
+""" "_": QUd- or <post-quote> or [[ZZZ-]];
 
 % Using backtic.x and backtic.y in the above definitions multiplies the
 % number of linkages by 2^(number of backtics). So it is treated as a
diff --git a/data/en/4.0.dict.m4 b/data/en/4.0.dict.m4
index 0f4bbee658..3719c333a8 100644
--- a/data/en/4.0.dict.m4
+++ b/data/en/4.0.dict.m4
@@ -10875,7 +10875,8 @@ RIGHT-WALL: RW- or ({@Xca-} & [[Xc-]]);
 
 % [[ZZZ-]]: link to "random" quotation marks that show up "for no reason".
 % Cannot use a blanket W+ here to pick up all W connectors, because ... ??
-""": QUd- or <post-quote> or [[ZZZ-]];
+% Underbar used like a quote-mark, e.g. for _bold text_
+""" "_": QUd- or <post-quote> or [[ZZZ-]];
 
 % Using backtic.x and backtic.y in the above definitions multiplies the
 % number of linkages by 2^(number of backtics). So it is treated as a
diff --git a/data/en/corpus-fixes.batch b/data/en/corpus-fixes.batch
index afd59ce95a..e45a03d935 100644
--- a/data/en/corpus-fixes.batch
+++ b/data/en/corpus-fixes.batch
@@ -4321,6 +4321,8 @@ Sweat stood on his brow, fury was bright in his one good eye.
 ¿this is a question?
 ¡this is an exclamation!
 
+Underbars are used for _bold text_.
+
 % Crazy UTF8 dashes
 we are dealing with androcentric—that is to say, male-dominated—concepts
 we are dealing with androcentric--that is to say, male-dominated--concepts