A term for an abnormally sized shit, typically even larger than a duke. Arch is used in order to emphasize size and the significance of the occasion
Person 1: Man you were in the bathroom for 15 minutes, what were you doing?!

Person 2: uuugh, I just had to drop an Arch Duke in there, try to avoid stall #3
by -tye- April 2, 2009
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while performing fellatio, one holds a lighter to his/her partner's genitals
tom gave jill the arch duke singe and she dumped him
by vladimir February 24, 2004
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