Green’s Dictionary of Slang

1. (US black/campus) to move, to go, to leave.

1938		‘Sl. among Nebraska Negroes’ in AS XIII:4 Dec. 317/1: To motivate down the thoroughfare means to walk along some widely frequented street, as along 24th Street in Omaha.
1985		Eble Campus Sl. Oct. 7: motivate – to move, go, leave, bolt; usually in a hurried manner.
1991		Eble Campus Sl. Mar.
2000		(con. 1940s–60s) Décharné Straight from the Fridge Dad 132: Motivate your piechopper Start talking.

2. (US black) to force oneself to do something that one dislikes.

1994

(con. 1960s) C. Major Juba to Jive.

3. (US campus) to move around in a group, socializing.

1979		Eble Campus Sl. Mar. 5: motivate – to mingle in a crowd, to socialize.
1996		Eble Sl. and Sociability 42: They also enjoy creating mock learned words that sound like polysyllabic borrowings from Greek or Latin: motivate or motorvate ‘move around socializing in a group’.