oink out, v. — Green’s Dictionary of Slang

oink out v.

[oink, onomat. for a pig’s grunt, var. on pig out under pig v.¹]

(US) to overeat.

1988		Right On! June 60: Speaking of oinking out,...they served bagels for breakfast [HDAS].
1990		Newsweek Special Issue: New Teens 60: His weight shot up—‘I oinked out,’ he says [HDAS].