YGTBFSM: Acronym for "You('ve) Got to be Fucking Shitting Me". Likely military origin.
Troop 1: We're getting recalled for a squadron-wide piss test.

Troop 2, just returning from Amsterdam: You've got to be fucking shitting me (YGTBFSM).
by poopoopeepeedaddy December 20, 2013
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