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1. Thumble
When your girlfriend texts your wife thinking it's you. like Bret Favre or Tiger Woods.
She just thumbled the invite.
2. Thumble
A portmanteu of thumb and stumble, works best when used with up or down to signify delight or disgust about a page using the Stumble Upon toolbar.
"dude, shit's cash, thumble up"

"ewww, no more Nailin' Palin for me, thumbled down"
3. Thumble
To make a typo while inputting text on a hand held device such as a cell phone.
"Hey guys, gow ard yot?"

"Sorry, I mean, how are you? Whoops, looks like I thumbled!"
4. Thumble
portmanteau of Thumb and Rumble, a slang word purportedly used in online gaming.

Seen in a badly researched episode of CSI, where a fat gamer is murdered
"Whenever he's bored, he just goes online. there's always someone looking to thumble"
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