Green’s Dictionary of Slang

1. (US black) a pocket.

1944

D. Burley N.Y. Amsterdam News 13 May 6B: His hideaways were slashed like canteloupe.

2. (N.Z. prison) a member of the Highway 61 biker gang.

2001

D. Looser Boobslang [U. Canterbury D.Phil. thesis] 86/2: hideaway n. a Highway 61 gang­ member.