diff --git a/dictionaries/sample.xml b/dictionaries/sample.xml
index 85233b63a..ad98f2b6f 100644
--- a/dictionaries/sample.xml
+++ b/dictionaries/sample.xml
@@ -2,7 +2,9 @@
      for use by the Latin IME.
      The format of the word list is a flat list of word entries.
      Each entry has a frequency between 255 and 0.
-     Highest frequency words get more weight in the prediction algorithm.
+     Highest frequency words get more weight in the prediction algorithm. As a
+     special case, a weight of 0 is taken to mean profanity - words that should
+     not be considered a typo, but that should never be suggested explicitly.
      You can capitalize words that must always be capitalized, such as "January".
      You can have a capitalized and a non-capitalized word as separate entries,
      such as "robin" and "Robin".
@@ -13,4 +15,3 @@
   <w f="128">sample</w>
   <w f="1">wordlist</w>
 </wordlist>
-