by Michael B. Quinion and Ruth Bygrave
     [This is a fast-access FAQ excerpt.]

The word "merkin" is one of the perpetual bad puns of the
Internet.  It actually means "pubic wig" (such wigs are used,
apparently, in the theatrical and film worlds as modesty devices in
nude scenes).  It can also be a contrivance used by male
cross-dressers designed to imitate the female genitals, or, as Eric
Partridge delicately puts it, "an artificial vagina for lonely men".
The OED dates it 1617 in the sense "pubic wig"; the origin is

   Then "merkin" was coined afresh to mean "an American", because it
sounds a bit like the half-swallowed pronunciation of "American" by
some Americans, particularly President Lyndon Johnson; and the fact
that it had a "naughty" meaning didn't hurt.  Punning use of the
word dates back to at least the early 1960s.  Bill Fisher writes:
"I'd guess multiple re-invention is going on here.  When I was
fooling around with the Orange Blossom Playhouse in Orlando, FL,
about 1963, we were amusing ourselves with trying to change a word
here or there in the play 'Teahouse of the August Moon' -- without
really screwing anything up -- and one guy cracked the cast up one
night when instead of the line 'But ... but ... he's an American!'
he said 'But ... but .. he's a Merkin!'  (The cast had been
laughing for a week or two about the definition of 'merkin' that
someone had found in a dictionary.)"

   One of Peter Sellers' roles in Stanley Kubrick's 1964 film Dr.
Strangelove was U.S. President Merkin Muffley.  This gets two
risque' locutions past the censor at once, since "muff" is another
slang term for female genitals or pubic hair (as in "muff-diving"
for cunnilingus).  This name was presumably the work of Kubrick or
his scriptwriter Terry Southern.  The film was based on the 1958
novel Two Hours to Doom (titled Red Alert in the U.S.), by Peter
George, pseudonym of Peter Bryant (1924-1966).  The novel was
serious -- Bryant had served in the RAF -- and does not name the
presidential character.  But when Kubrick filmed it as a satire,
Bryant was so convinced that he then re-novelized the film.

   On Usenet, "merkin" is only a few years old.  A few people recall
alt.fan.pratchett (a newsgroup dedicated to the writings of Terry
Pratchett, a British writer of humorous fantasy) as the origin, but
Matthew Crosby (crosby@nordsieck.cs.colorado.edu) writes:  "I
believe I was the original person to use 'Merkin' in AFP (certainly
it was my use of the word that started the large thread on it), and
I'm sure that 'Merkin' was being used before that as an underhand
insult.  By me, if nothing else."

   "Merkin" is now widely used on Usenet to designate Americans
(especially by non-Americans).