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A girl who hangs out in ventrilo servers, commenting on other people's ranting, especially the administrators. A tumbum often makes up unnecessary nicknames for her ventrilo associates, such as bumbum.
Gristan: "A Jewish missionary went to Africa to educate a tribe of pygmies called Trids. After a few weeks, during the first full moon, the Rabbi-..."

Mina: "omg rant rant rant rant I don't care"

Gristan: "Mina, stop being such a tumbum"
by WednesdaysComing July 22, 2008
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