barney

barney n.  In Commonwealth hackish, `barney' is to
   {fred} (sense #1) as {bar} is to {foo}.  That is, people
   who commonly use `fred' as their first metasyntactic variable
   will often use `barney' second.  The reference is, of course, to
   Fred Flintstone and Barney Rubble in the Flintstones cartoons.