rhythm, n. — Green’s Dictionary of Slang

rhythm n.

[play on blue n.¹ (4a)/SE rhythm and blues]

(drugs) amphetamine.

1970		R. Gilmore Drug Education Hbk.
1977		L. Young et al. Recreational Drugs.
2001		ONDCP Street Terms 18: Rhythm — Amphetamine.

give up rhythm (v.)

(US black) for a woman, using body language, to indicate her sexual availability to a man with whom she is walking or dancing.

1981

A.K. Shulman On the Stroll 31: The way you been makin up to me and givin up rhythm, I thought sure we’d be spendin time together.