Green’s Dictionary of Slang

1. (US) a lazy or stupid person.

1866		‘Edmund Kirke’ Guerillas 43: [Fetters] for this young hyena? [HDAS].
1919		DN V 70: If I ever make a hyena of myself, I wish you would tell me.
1927		(con. 1910s) S. Lewis Elmer Gantry 356: Rich old hyenas who never went to church.
1933		J.T. Farrell Gas-House McGinty 190: Put up or shut up, you fat hyena!
1933		C. Drew ‘Sledgehammer Joe’ in Bulletin (Sydney) 19 July 48/3: ‘[T]here’ll be a percentage ol the local hyenas nutty enough to back Murray’.
1944		D. Runyon Runyon à la Carte 118: Or are all dramatic critics just naturally hyenas, as I suspect?
1953		(con. 1942) L. Uris Battle Cry (1964) 193: Jest take it slow and easy, pard. We’ll meet them hyenas in plenty of time.

2. (N.Z. prison) one who leeches off their friends and if borrowng money, fails to repay it.

2001

D. Looser Boobslang [U. Canterbury D.Phil. thesis] 91/2: hyena n. = seagull.