Green’s Dictionary of Slang

1. (Aus.) anything simple [var. on SE piece of cake].

1924		News (Adelaide) 28 Jan. 2/3: Today’s [race was] a soft snack for him.
1934		Sydney Sportsman 27 Jan. 6/2: One of the two-year-old races on a suburban course would be a snack to Subsidy, and you can bet your shekels that Danny won’t be long in placing him to advantage.
1941		Baker Popular Dict. Aus. Sl. 68: Snack, a certainty.
1944		Lithgow Mercury (NSW) 17 Mar. 2/1: Such being the circumstances, the two soldiers may have a strong motive for not wanting a discharge, preferring to cope with the sergeant-major, who would be a snack in comparison.
1953		T.A.G. Hungerford Riverslake 31: You’ll find it a snack, if you don’t mind a bit of work.
1969		A. Buzo Rooted III iv: Hammo’s got a thriving little outfit, don’t you worry. Buying and selling, supply and demand. It’s simple. Wholesale and retail. It’ll be a snack.
1993		Smith & Noble Neddy (1998) 217: We followed their movements for two weeks and decided it was a snack.

2. (US black) the penis, often when small [its role in oral sex].

1974

H.L. Foster Ribbin’, Jivin’, and Playin’ the Dozens in Major (1994).

3. (juv.) an attractive girl.

2024

Axis Parents’ Guide to Teen Sl. 🌐 Snack = An attractive person. ‘Girl lookin’ like a snack!’.