A word consists of a string of characters terminated by a set of
 delimiter characters.  The default delimiter characters are spaces,
 tabs, carriage returns, line terminators, line feeds, formfeeds, and
 vertical tabs. Spaces are handled in a special way:  all spaces
 following a word up to the first non-space character are considered part
 of a word.  Other delimiters are not considered  part of the word they
 terminate.  Rather, they are considered to be words by themselves,
 unless SET WORD NODELIMITER in in effect. If SET WORD NODELIMTER is in
 effect, delimiters are not considered words by themselves but are
 considered part of the word they terminate. The three word entities are:

     W   Specifies the entire word in which the cursor is positioned.
     BW  Specifies all characters preceding the cursor up to the beginning
         of the word.
     EW  Specifies all characters from the cursor through the end of the
         word.

 You can change the word delimiters with the SET ENTITY command.