diff --git a/README.md b/README.md
index 6eb35cd..ecf09fa 100644
--- a/README.md
+++ b/README.md
@@ -222,8 +222,8 @@ If set, clac will search for `$HOME/.config/clac/words`.
 
 ### How to define words
 
-Words are defined as aliases, with one alias on each line. Empty
-lines and lines starting with `#` are ignored. Here are some examples:
+Words are defined as aliases, with one alias on each line.
+Empty lines are ignored. Here are some examples:
 
 ```shell
 pi 3.14159265358979323846
@@ -251,6 +251,22 @@ $ clac "42 dup * pi *"
 5541.76944093239
 ```
 
+### Comments
+
+Any lines that begin with `#` are considered comments and
+are ignored. There are no inline comments, and any `#`
+characters that are not the first character of a line are
+interpreted literally. To define `#` as a word, wrap it in
+double quotes in the definition:
+
+```shell
+# This is a comment.
+"#" count
+```
+
+The first line is ignored, and the second line assigns `#`
+to the operation `count`.
+
 ### How to list defined words
 
 If you type `words` and hit enter, clac will list the defined words.
diff --git a/clac.1 b/clac.1
index ad6a412..732dc4e 100644
--- a/clac.1
+++ b/clac.1
@@ -251,6 +251,26 @@ User defined words can be used as if they were built-in commands:
 .Dl $ clac Qq "42 dup * pi *"
 .Dl Sy 5541.76944093239
 .
+.Ss Comments
+.
+Any lines that begin with
+.Sy #
+are considered comments and are ignored. There are no inline comments,
+and any
+.Sy #
+characters that are not the first character of a line are interpreted
+literally. To define
+.Sy #
+as a word, wrap it in double quotes in the definition:
+.Pp
+.Dl # This is a comment.
+.Dl \(dq#\(dq count
+.Pp
+The first line is ignored, and the second line assigns
+.Sy #
+to the operation
+.Sy count.
+.
 .Ss How to list defined words
 .
 If you type `words` and hit enter, clac will list the defined words.