Green’s Dictionary of Slang

jigger! excl.

also gigger (me)! jigger me tight! jiggers!
[? a euph. for Jesus! excl., although usu. used in v. forms; ? semi-euph. for bugger v.1 ]

1. used as a vaguely indecent oath, e.g. as by jiggers! jigger it! be jiggering well careful! etc.

[UK]J. Burrowes Life in St George’s Fields 17: Why gigger me if my master didn’t give me an order for common Garden last week.
[Ire] ‘The Charity Boy’ Dublin Comic Songster 165: To cut avay ’tis then the time, / Oh, jigger me tight! it is so prime.
[UK]Dick and Sal 22: Jigger! I would buy har a ribbin.
[UK]Broad Arrow Jack 22: Oh, blow your weakness! dash your helplessness, and jigger your happetite!
[UK]A. Binstead Gal’s Gossip 27: I fancy I can hear you reply ‘Oh, jigger it!’ as a sweet girl friend of mine, who is too lady-like to swear [...] remarked.
[US](con. 1910s) J.T. Farrell Young Lonigan in Studs Lonigan (1936) 70: ‘Jiggers!’ yelled Johnny O’Brien.
[US]Hecht & Fowler Great Magoo 61: Jiggers, my manager!

2. (US, also jigaroo! jigeroo!) a warning that someone hostile, e.g. the police, a teacher, one’s parents, is coming.

[US]L. Pound ‘A Second Word-List From Nebraska’ in DN III:vii 545: jigger, v. Look out; be careful. ‘Jigger, kids, the teacher’s coming.’.
[US]A. Berkman Prison Memoirs of an Anarchist (1926) 179: Now, jigaroo, screw’s comin’.
[US] ‘Jargon of the Und.’ in DN V 452: Jigeroo, A warning that the police are coming.
[US]H. Yenne ‘Prison Lingo’ in AS II:6 280: An inmate will say in warning to another, ‘Jigger, a screw,’ meaning ‘Be careful. A guard is coming’.
[US]F.M. Thrasher Gang 267: ‘Jiggers!’ — ‘Run, the cops are coming!’.
[US]L.W. Merryweather ‘Argot of an Orphans’ Home’ in AS VII:6 403: Jiggers, the stick’s coming.
[US]W. Pegler in Nevada State Journal (Reno) 21 Dec. 6/3: The almanac also tells us [...] that the word jiggers is a cry of alarm denoting the approach of the cops.
[US]Monteleone Criminal Sl. (rev. edn) 132: jiggers A warning; warning of the approach of a policeman.
[US]Goldin et al. DAUL 110/2: Jigger. [...] an exclamation of warning. [...] Jiggers! A danger signal to stop what one is doing or make a getaway.
[US]P. Crump Burn, Killer, Burn! 104: Jiggers! [...] Somebody has come in.

In phrases

give jiggers (v.) (also give jiggs)

(US) to be a lookout, to keep a lookout.

[US]C.R. Shaw Jack-Roller 16: I and two other guys waited close to the alley [...] We were going to give ‘jiggers’.
[US](con. 1910s) J.T. Farrell Young Lonigan in Studs Lonigan (1936) 130: Benny Taite suddenly gave jiggers.
[US]H.C. Woodbridge ‘Miscellany’ in AS XXXVI:3 228: jiggs, jiggers, give, v. phr. To give a warning.
[US]J. Blake letter 22 June in Joint (1972) 228: Hey lefty, I’ll give ya jiggers. I’ll be lookout, okay, boy?

In exclamations

by jiggers! (also by jickers! by jiggurs! by jigs! by ziggity!)

(orig. US) a mild oath, euph. for by Jesus!

[UK]Leeds Times 3 Apr. n.p.: ‘Jolly Tosh’ [...] had finished his famous song, ‘Oh, by Jiggers! we are Niggars!’.
[UK]Binstead & Wells A Pink ’Un and a Pelican 209: By jig’s, here he is again!
[UK]A. Binstead Pitcher in Paradise 29: By jigs, never knew time slip by so quickly.
[US]A.G. Field Watch Yourself Go By 351: By jiggurs, ef he ain’t wearin’ Mary’s [...] green silk stockin’s.
[US]J.F. Dobie Rainbow in Morning 92: By jiggers.
[US]Z.N. Hurston Bone of Contention (1995) 978: By ziggity, dat ol’ mule been dead three years an’ still kickin’.
[US]L. Sage Last Rustler 31: But by jickers, I reckon I could try.