Green’s Dictionary of Slang

1. (US) a country dweller.

1911

Wash. Post 10 Dec. 4/5: A ‘whisker’ is a countryman.

2. (orig. US) a very small, infinitesimal amount or distance.

1898		F.P. Dunne Mr Dooley in Peace and War 78: He bate th’ cat to th’ windy be a whisker.
1913		G.D. Chase ‘Lists From Maine’ in DN IV i 6: whisker, n. A little; a trifle. ‘Move it just a whisker.’.
1953		A. Buckeridge Jennings’ Diary 110: I haven’t seen a whisker of a prehistoric remain yet.
1971		A. Buzo The Roy Murphy Show (1973) 125: Country to win by a whisker.
1999		Indep. Rev. 23 July 13: I’m a whisker away from 30 now.
2000		Indep. Rev. 5 May 12: I wrote a screenplay and it came within a whisker of selling.

3. a young woman.

1928		Hecht & MacArthur Front Page Act III: Can you imagine Butch laying up with some whisker at the Revere House!
1941		S.J. Baker Dict. Aus. Sl. 81: whisker, a girl or young woman.
1950		‘No 35’ in Simes DAUS 212/1: whisker [...] (iii) A girl or young woman.
1960		Wentworth & Flexner DAS 575/2: whisker (taboo) [...] A woman considered solely as an object of sexual gratification; a promiscuous woman; a prostitute.
1966		Trimble 5000 Adult Sex Words and Phrases.

4. the female pubic hair.

1788		implied in whisker splitter below.
1939		H. Miller Tropic of Capricorn (1964) 192: Rita too was hot under the whiskers.
1950		‘No 35’ in Simes DAUS 212/1: whisker [...] (ii) Pudenda feminae (a capellis pubis).

5. the penis.

1999

D. Lypchuk ‘A dirty little story’ in eye mag. 8 July 🌐 The two of them dabbed the brush, danced the goat’s jig, dug in the whisker and swept the chimney until, just as he was about to do her a kindness, his sweater fell off and he had to put a new willy-welly on.