Green’s Dictionary of Slang

(US campus) someone who mistakenly thinks that they are impressive; something considered socially unacceptable.

1989		P. Munro Sl. U. 57: cheez whiz 1. out-of-date, cheesy. 2. something that’s out-of-date or cheesy.
1996		Eble Sl. and Sociability 70: Cheese became a metaphor for ‘something unattractive or undesirable’ and gave rise to cheeseball, cheezy, velveeta, cheese whiz.