Biffing the cheddar is an ambiguous way of being coy about an action you will or have performed. These acts may be innocent, but are often conveyed with a sexual undertone.
Bro, I spent all night biffing the cheddar to Christi Boner.

Yo Alex! Hurry up in the shitter! What are you- biffing the cheddar in there!?
by GJ_Jerry_G August 12, 2023
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