Green’s Dictionary of Slang

study v.

1. (W.I./UK black) to think about.

[UK]C. Chesnutt ‘The Gray Wolf’s Ha’nt’ in Conjure Woman 173: En Dan kep’ on studyin’ ’bout dis ’tel he got so he did n’ ha’dly das’ ter eat er drink fer fear dis cunjuh man had p’isen de vittles er de water.
[US]R. Fisher Walls Of Jericho 14: Aw go ’haid, drabble-tail. Ain’ nobody studyin’ yo’ family.
[UK]J. Curtis They Drive by Night 223: You want to study me a bit and all. It’s all very well for you. You don’t seem to mind having a game of hide and seek. Where do I come in?
[UK]S. Selvon Lonely Londoners 139: He must be still studying that girl what let him down.
[US]M. Braly Shake Him Till He Rattles (1964) 121: I’m not studying no oil-burner of a habit and a hundred-dollar nut every day.

2. (gay) to appraise a potential sexual conquest or partner.

[US]J.P. Stanley ‘Homosexual Sl.’ in AS XLV:1/2 58: study v Look someone over with sexual intent in an obvious manner.

3. (US campus) to indulge in sexual caresses short of intercourse.

[US]Baker et al. CUSS 205: Study To neck.

SE in slang uses

In compounds

study mongrel (n.) (also study hog)

(US campus) someone who studies hard.

[US]Eble Campus Sl. Oct. 4: study hog – someone who studies constantly and has no social life.
[US]Eble Sl. and Sociability 69: A study mongrel is ‘someone who studies hard’.

In phrases