Green’s Dictionary of Slang

feague v.

also fegue, fig
[SE feague, to beat, to whip; ult. Ger. fegen, to polish]

1. to have sexual intercourse.

[UK]Etherege She Would if She Cou’d III iii: Let us get ’em To lay aside these masking Fopperies, and then We’ll fegue ’em in earnest. [...] Love and Wenching are Toys, / Fit to please beardless Boys, / Th’are sports we hate worse than a Leaguer; / When we visit a Miss, / We still brag how we kiss, / But ’tis with a Bottle we fegue her.
[UK]Dorset ‘A Faithful Catalogue of our most Eminent Ninnies’ in Works of Rochester, Roscommon, Dorset (1720) 31: Her noble Protestant has got a Flail, / Young, large and fit to feague her briny Tail.

2. to enliven, usu. of a horse.

[UK]Grose Classical Dict. of the Vulgar Tongue n.p.: Feague, to feague a horse, to put ginger up a horse’s fundament, to make him lively and carry his tail well.
[UK]Grose Classical Dict. of the Vulgar Tongue ms. additions n.p.: To feague a horse; to put ginger up a horse’s fundament, & formerly a live Eel.
[UK]Grose Classical Dict. of the Vulgar Tongue (3rd edn) n.p.: Feague. To feague a horse; to put ginger up a horse’s fundament.
[UK] ‘Modern Dict.’ in Sporting Mag. May XVIII 100/1: Feague, to feague a horse, to put ginger up a horse’s fundament, and formerly, as it is said, a live eel, to make him lively and carry his tail well.
[UK]Lex. Balatronicum [as cit. 1796].
[UK]‘Jon Bee’ Dict. of the Turf, the Ring, the Chase, etc. 75: To Feague a horse — formerly a live eel was used, ginger being then dear. [Ibid.] 76: Fig, figged — ginger; little lumps whereof are thrust into the rectum of horses to give them a short-lived vigour; they are then said to be figged.
[UK]R.S. Surtees Handley Cross (1854) 426: ‘He is [...] up to any weight, and quiet—’ ‘Quiet enough,’ observed a bystander, ‘if you hadn’t figged him’.