Green’s Dictionary of Slang

lap v.

also lap up
[fig. use of SE lap v./lap n.2 (2)]

1. to drink alcohol, esp. greedily.

[UK]‘One of the Fancy’ Tom Crib’s Memorial to Congress 21: Up he rose in a funk, lapp’d a toothful of brandy, / And to it again.
[UK]Duncombe New and Improved Flash Dict.
[UK]W. Bradwood O.V.H. II 110: The latter lapped his third go of cold gin at the bar of the Greyhound.
[Aus]Bulletin (Sydney) 30 Apr. 9/4: We know where there is some grand whisky in a keg—shoulder arms and we’ll lap it.
[UK] ‘’Arry’s Spring Thoughts’ in Punch 17 Apr. 185: And ’aving jest landed a race, I was lapping a bottle of fizz.
[UK] ‘’Arry on Wheels’ in Punch 7 May 217/2: We lap up a rare lot of lotion [...] in our spins out of town.
[UK]‘Doss Chiderdoss’ ‘Deceptive Labels’ Sporting Times 4 Mar. 1/4: He was told ’twas labelled ‘poison,’ which but strengthened his belief / That some brand of whisky therein was on tap; / For with many ’twas a dodge to frighten off a would-be thief / Who might otherwise the precious liquor lap.
[UK]‘Bartimeus’ ‘Narrative of Commander W.D. Hornby’ in Awfully Big Adventure 120: Lord knows why I should have been rammed up in bed while all you pirates lapped up bubbly and made a night of it.
[US]M. Bodenheim Georgie May 63: Lazing aroun’ [...] and lapping booze.
[US]R. Chandler ‘Nevada Gas’ in Spanish Blood (1946) 165: He lapped up too much corn getting set for the job.
[US]E. O’Neill Iceman Cometh Act IV: I’ve lapped up a gallon, but it don’t hit me right.
[US]‘Bill O. Lading’ You Chirped a Chinful!! n.p.: Lapping: Quaffing beer in vigorous fashion.
M. Millar An Air That Kills (2016) 344: Poor old galloway, sitting down there [...] while we’re up here lapping up his liquor.

2. (UK Und.) to take, to steal.

[US]Matsell Vocabulum 50: lap [...] pick it up; to take; to steal.
[Aus]C. Crowe Aus. Sl. Dict. 44: Lap, to pick up, to steal.

3. to enjoy greatly; usu. as lap it up.

[UK]E.J. Milliken ’Arry Ballads 62: I lap lemon-squash.
[Aus]Bulletin (Sydney) 30 Oct. 14/4: They must love something, so they lavish their affection on this large, soft infant. It is ‘Hand me my manuscript, darling,’ and ‘You may have my theory-book, dear,’ and ‘Are you going into Interpretation, duckie?’ And Tom laps it up.
[US]W. Brown Teen-Age Mafia 5: Feeding his line to the kids who lounged around the joint. They were lapping it up.
[Aus]J. Hibberd White with Wire Wheels (1973) 89: Boy, is she lapping it up!
[UK]S. Berkoff East in Decadence and Other Plays (1985) 69: She stirred just ever so little it was but she knew I was lapping it up.
[UK]S. Berkoff West in Decadence and Other Plays (1985) 120: I lap it up.
[UK]K. Sampson Powder 50: Go at it, head down, live fast, lap it up.
[UK]Indep. Rev. 21 Jan. 5: They will just lap it up.

4. to perform cunnilingus [note lap n.1 /cunt-lapper n.].

[UK]B. Naughton Alfie II ii: lacey: Where’d you lap it up, mate? lofty: I didn’t lap it up. I gave the young lady a lift from Sheffield.
[US]‘Troy Conway’ Cunning Linguist (1973) 100: Completely de-vodca’ed and all lapped out and licked cleaner than Lassie’s plate of Red Heart, Magda sagged against my chest.
[US]L. Pettiway Workin’ It 219: I had this bitch lap up on this pussy.

5. to be very fond of.

[Scot]I. Welsh Trainspotting 85: Dinnae git us wrong, ah lap the cunt up.

SE in slang uses

In phrases

lap the gutter (v.) [? either gutter-alley under gutter n. or gatter n.]

to drink; to get drunk.

[UK]‘Ducange Anglicus’ Vulgar Tongue.
[UK]London Standard 13 Dec. 3/3: When he has lapped the Gutter, and Got the Gravel Rash [...] not till then is he entitled, in vulgar society, to the title of Lushington, or recommended to Put in the Pin.
[UK]Sl. Dict.
[UK]Farmer & Henley Sl. and Its Analogues.
[US]Sun (NY) 5 Mar. 4/6: He has got the gravel rash [...] he has lapped the gutter.