@findex define-global-abbrev
You can define an abbrev without inserting either the abbrev or its
expansion in the buffer using the command @code{define-global-abbrev}.
-It reads two arguments--the abbrev, and its expansion. The command
+It reads two arguments---the abbrev, and its expansion. The command
@code{define-mode-abbrev} does likewise for a mode-specific abbrev.
To change the definition of an abbrev, just define a new definition.