(noun) The feeling that is obtained after watching the new Transformers movie. It is a feeling of pure joy, exhilaration, and "holy shit I wish my car could do that"-ness. (Side note: a side effect of a transformergasm is often a REAL orgasm)
"OHMYGAWD dude, watching Optimus battle Megatron just gave me the biggest transformergasm EVER!"
by JOE DAVIS! August 10, 2007