Green’s Dictionary of Slang

1. (US campus) an offensive or unattractive person.

1978		UTSQ n.p.: [Unattractive male]. ..dog,...honker [HDAS].
1982		L. Glass Valley Girl 58: Shine that...honker [HDAS].
a.1990		Univ. Tenn. student n.p.: A honker is a socially unpleasant individual [HDAS].

2. (US teen) anyone considered odd or eccentric.

1982

M. Pond Valley Girl’s Guide to Life 58: Honker — Someone weird [HDAS].