lather, v. — Green’s Dictionary of Slang

lather v.

[SE in 20C+]

1. to thrash.

a.1790		C. Dibdin ‘Patrick O’Row’ in Collection of Songs II 52: Ah honey ’twould do your heart good / To be lathered by Patrick O’ Row.
1816		W.T. Moncrieff All at Coventry I ii: So so! This fine striking science turns out to be fighting after all. No occasion to larn Tommy that; he knows how to lather well enough.
1821		‘A Real Paddy’ Real Life in Ireland 52: ‘Lather away wid your oak stick!’ was the cry.
1830		W.T. Moncrieff Heart of London II i: He’ll force me to lather him soon.
1837–8		‘Wry-Mouth Bob And His Jolly Red Nob’ in Cuckold’s Nest 46: When a female wandered to his stall, / His long tool would display, / Then her leather he’d scan, like a jolly good man, / And at it he’d lather away.
1843		Satirist & Sporting Chron. (Sydney) 8 Apr. 3/2: Why don’t you lather him, Ellen? you are big enough.
1844		J. Overs Evenings of a Working Man 187: [to a dancer] ‘Braa-vo Poll! Larther away’.
1849		Punch’s Almanack in Farmer & Henley Sl. and Its Analogues IV (1890–1904) 160/1: To dream of soap betokens a combat in which you may expect to get lathered.
1859		Wkly Varieties (Boston, MA) 3 Sept. 3/4: Deserving of the Lash [...] Sentence — the whip to be first soaked in pickle, and then used to lather him until he yells aloud for mercy.
1866		J. Greenwood Little Ragamuffin 185: You wouldn’t go a-latherin’ of him — would you, Jim?
1877		‘Paddy, The Ladies’ Darling’ in Laughing Songster 49: While I was lathering away at the tough devil.
1896		A. Morrison Child of the Jago (1982) 71: ’E ups an’ lathers you with ’is belt.

2. to flatter.

1845		R.S. Surtees Hillingdon Hall I 262: Arter I’ve lathered and soaped the chaps well, I shall want some one to shave them.
1853		N.Y. Clipper 2 July 2/2: Salvi soaped and lathered us, until we had to dip into him,.

3. to defeat.

1866

G. Townshend Non-Combatant 262: We’re lathered, that’s the long and short of it [...] we’re beat [HDAS].

In phrases

lather up (v.)

(US) to show affection, to encourage, to excite; esp. of a woman prior to seduction.

c.1930		(con. late 19C) N. Kimball Amer. Madam (1981) 191: You’re always [...] having to lather the boys up a bit and curry them down when they get back.
1965		(con. 1944) E.M. Nathanson Dirty Dozen (2002) 116: He had never wanted for money for [...] lathering up some dame.