Green’s Dictionary of Slang

amyl n.

[abbr.]

(drugs) amyl nitrite.

[UK]E.W. Hornung A Thief in the Night (1992) 367: ‘Amyl – get me amyl!’ he gasped.
[UK]T. Taylor Baron’s Court All Change (2011) 34: Someone cracked an amyl.
[US]R. Price Ladies’ Man (1985) 244: It’s amyl, man, it’s lightweight.
[US] Spears Sl. and Jargon of Drugs and Drink (1986).
[Aus]Campaign (Sydney) Sept. 23/2: [personal ad.] Guy 35, slave [...] needs leather master into Amyl, B/D, toys, S/M, cockrings, butt plugs and whatever you wish to force your miserable slave to do [Simes:DLSS].

In compounds