Green’s Dictionary of Slang

1. LSD.

1969		R.R. Lingeman Drugs from A to Z (1970).
1982		AS LVII:4 289: A sampling of current names for varieties of LSD would include [...] the hawk.
2001		ONDCP Street Terms 11: Hawk — LSD. [Ibid.] 21: The Hawk — LSD.

2. an LSD user.

1971

E.E. Landy Underground Dict. (1972).

3. an LSD seller.

1971

E.E. Landy Underground Dict. (1972).