Green’s Dictionary of Slang

(US drugs) heroin.

1967		P. Thomas Down These Mean Streets (1970) 109: I saw they were snorting tecata. I smoked marijuana, which was just like smoking cigarettes, but I was down on drugs.
1971		E.E. Landy Underground Dict. (1972).
1989		J. Morton Lowspeak.
2001		ONDCP Street Terms 21: Tecata (Spanish) — Heroin.