A 'polite' term for the male or female anus. See puckered rosebud
I say! You! You Hugh! Hugh Grant, you're a bit of a, that is if you don't mind my observing, if it's not too much trouble etc you're something of a fundamental orifice you old stick you!
by Mark November 25, 2003
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A polite way of explaining that someone is the c word for female anatomy
Jeremy is being a fundamental orifice.

Stop being a fundamental orifice.
by Kenny loggins August 27, 2023
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