it's a combonation of 2 different phrases.... "thing a majig" and an old Marine Corps word that we used to describe something when we couldn't think of the name of it "who'yah".
shanna: bay bay, where u put my cellphone charger?

scooby: it's sittin' on top of the thing'a'ma'ya (box) on the kitchen table.

scooby: say bruh, hand me that thing'a'ma'yah (wrench) so i can take this bolt loose
by big scooby March 30, 2010
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