Green’s Dictionary of Slang

chum v.

[chum n. (1); verb use coined by John Wesley (1703–91) in 1730]

1. to put someone in a position of sharing accommodation, esp. in a prison cell.

[UK]Proceedings at Sessions (City of London) July 171/1: The Prisoner had been my Chum in the Fleet-Prison [...] I had desired the Chamberlain to let me be removed, but the House was then so full that I could not be chum’d elsewhere.
[Aus]Examiner 18 Dec. 4/2: There were other prisoners without a chum, who ought to have been chummed before me.
[UK]Dickens Pickwick Papers (1999) 542: You’ll be chummed on somebody to-morrow.
[UK]J. Grant Sketches in London 52: When a prisoner is first confined within the walls, he is entitled to what is termed a ‘chum ticket,’ which is a small piece of paper on which one of the officers of the prison, called the chum-master, writes the name of the party, with the number of the room in which he is to be ‘chummed’.
[UK]T. Hughes Tom Brown’s School-Days (1896) 84: You’ll be chummed with some fellow on Monday, and you can sit here till then.
C, Mackay Life & Liberty in America I 28: ‘Bunk together?’ ‘Yes; bunk, sleep, chum, live together’.
[US]L.H. Bagg Four Years at Yale 43: Chum, a roommate or particular friend [...] Chum is used also as a verb.
[UK]A. Griffiths Fast and Loose III 208: You’ll have to chum with Devas here now that Dellew’s gone.
[Aus]‘Henry Handel Richardson’ Aus. Felix (1971) 4: They had chummed together on the seventy-odd-mile from Melbourne; had boiled a common billy and slept side by side.
[US]J. Spenser Limey 267: I was sorry ‘Spud’ had decided to chum with Castillo, but I suppose he thought I should be a dull cell mate.

2. (also chum in, chum it, chum up) to live with, to befriend.

Wesley in Works (1831) VI 597: There are... some honest fellows in College, who would be willing to chum in one of them .
[UK]C. Churchill Ghost Bk II n.p.: Old Maids and Rakes are join’d together. Cowuettes and Prudes, like April weather, Wits forc’d to chum with Common Sense [F&H].
[UK]Grose Classical Dict. of the Vulgar Tongue ms. additions n.p.: We Chumm’d together.
[UK]‘A. Burton’ My Cousin in the Army 163: A worthy—he and I for years Have ‘chumm’d’ together.
[UK]Swell’s Night Guide 68: She vent macadamizing again, and then she chummed vith a gonniff, and they took a crib and did the fence and bawdykin dodge.
[UK]A. Mayhew Paved with Gold 252: It was resolved among these boys that they should ‘chum’ together.
[UK]T. Hughes Tom Brown at Oxford (1880) 57: Then we fell in with a bird with mahogany tops, and, as usual, Drysdale began chumming with him.
[Aus]M. Clarke in Money Knocking About in N.Z. viii: This is the sort of young gentleman who [...] camps affably with the savages, ‘chums in’ with diggers.
[UK] ‘’Arry at the Royal Evening Fête’ in Punch 28 July 38/1: Ten bob and snap togs took me in, and I chummed with the very eleet.
[US]C.F. Lummis letter 28 Jan. in Byrkit Letters from the Southwest (1989) 267: These fellows that promise to chum it with us may peter out, but you and I stick together.
[Aus]Bulletin (Sydney) 26 July 9/1: Our Gracious has been chumming in with the somewhat disreputable ex-Queen Isabella at Windsor.
[UK]H.B. Norris [perf. Vesta Tilley] The Piccadilly Johnny with the little glass eye [lyrics] The set of boys I chum with are the best-known set down town.
[Aus]West Australian (Perth) 5 Feb. 9/3: He was now Bob Edwards, the unkempt tramp, humping his bluey along the Sunset Track [...] and chumming with the human flotsam and jetsam that is for ever floating about these out skirting fringes of civilisation.
[US]A. Adams Log Of A Cowboy 357: These old pioneers naturally hung together and visited and chummed with one another.
[UK]A. Wright Rung In (1931) 262: So you two have chummed up.
[NZ]Truth (Wellington) 6 Apr. 7/5: She chummed up with Abingdon Baird, a sport who owned a string of racers.
[UK]Marvel 3 Mar. 15: He must be a bit of an ass [...] to chum in with Donbrook and Elthorne, who only soap him for what they can get out of him.
[US]C. McKay Home to Harlem 126: The two grades, cooks and waiters, never chummed together, except for gambling.
[US]J. Dixon Free To Love 131: Is Danny chumming with Neil Neilson?
[UK]‘George Orwell’ Clergyman’s Daughter (1986) 91: You can chum in at our bin - four to a bin’s the best picking.
[Aus]Western Mail (Perth) 30 May 2/3: He chummed up with a Tommy batman over a few pints.
[US]S. Lewis World So Wide 164: Born here in Florry, but lived in England, and chummed with the Yankee troops here.
[US]S. King It (1987) 142: Not the people I chummed with.
[US]S. King Dreamcatcher 155: If you tell anybody I did this [...] I’ll never chum with you guys again.

3. (also chum in) to join in with.

[UK]Leaves from Diary of Celebrated Burglar 28/2: We ‘officed’ the other ‘gun’ to ‘chum in’ with us and have some ‘max’.
[UK]East & Sth Devon Advertiser 12 Sept. 3/4: Never go chumming with an Apache.
[US]W. Irwin Confessions of a Con Man 152: We chummed down to the station.
[UK]I. Welsh Glue 96: Spud jist chummed ays, eh explains.

4. to keep a lookout for someone.

[UK]J. Fagan Panopticon (2013) 205: ‘I need tae pee but’ [...] ‘Ill chum you.’ Tash and Isla wander of to the [...] shribs.

In phrases

chum along with (v.) (also chum around with, ...in with, ...up with)

1. to become friendly with.

[Aus]‘Rolf Boldrewood’ Robbery Under Arms (1922) 165: He might have chummed in with them, of course, or he might not.
[UK]E.W. Hornung Amateur Cracksman (1992) 122: To have chummed up with him would have been fatal.
[US]‘Hugh McHugh’ Out for the Coin 30: He chummed up with yo’ all at Gravesend.
[US]H. Green Actors’ Boarding House (1906) 280: She didn’t chum around with the rest much.
[UK]Magnet 3 Sept. 6: Fancy shutting out a chap they’re chumming with.
[Aus]Bulletin (Sydney) 12 Dec. 30/1: And he and Jones chummed up and drank / And got on very well; / Each held as much as any tank, / And had good yarns to tell.
[US]E. Ferber ‘That’s Marriage’ in One Basket (1947) 35: A fellow can chum around with you. Little pal.
[UK]Wodehouse Leave it to Psmith (1993) 496: I’d chummed up with a fellow who had been invited down to the place.
[UK]J.B. Booth London Town 240: Their friends ‘chummed’ up with the dancing instructresses.
[UK]M. Marshall Tramp-Royal on the Toby 63: If they catches me chumming with a bloke like you, they’ll arrest both of us on sight.
[Aus]K. Tennant Battlers 143: He chummed up with the guardian of the merry-go-round.
[UK]‘Charles Raven’ Und. Nights 43: Peter [...] chummed up with another bloody-minded character, one Joe Tasker.
[US]R. Prather Scrambled Yeggs 111: He was chumming around with homicidal heavies as if they were customers at a society bazaar.
[US]K. Marlowe Mr Madam (1967) 45: At school when we started to chum around, she’d been aware I was gay.
[US]R. Sabbag Snowblind (1978) 33: He and Holly were chumming around with Hollywood types.
[US]R. Price Breaks 156: I never chummed up to him.
[US]S. King It (1987) 142: Another kid that we chummed with – that I chummed with after Georgie died.
[UK]Guardian Weekend 5 June 34: They chummed along because there wasn’t anyone else.
[UK]Indep. 7 Mar. 7: Chumming up to the maitre d’ is a thing of the past.

2. (UK Und.) to work as an accomplice with.

[UK]E. Pugh City Of The World 276: Then they got more artful and clever. They chummed up with real swell workmen that passed things to ’em in a crowd.
chum with (sfx)

to accompany; to travel with.

[UK]Dundee Courier (Scot.) 1 Feb. 7/4: If your for London, I don’t mind chumming with you on the way.