What is Dumbit?
1.
a phrase that is a combination of "darn it" or "damn it" with "dumb", said when a girl accidentally walks into a tree branch and she mixes up her thoughts!
"Hey! Look out for that tree bench!"
"Huh?" (smack) "AHHH, DUMBIT!"
See
2.
another word for dumbass, can be used instead of cursing
That person is such a dumbit!
See