This is when a large woman spreads her legs while sitting down, however her thighs are too large to expose vagina, so they make a decieving extra layer of labia, hence the thooch=thigh+cooch.

Attritutes of a cooch (or snatch) and a thatch are visually comparable

(or thatch=snatch+thigh
Yo Kye, last night, uhh... did Buronikuh have a thooch/thatch?

Joey, look! That thooch/thatch is a blowin' in the wind.
by twizzlemynizzle February 21, 2011
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