The political gesture popularized by Bill Clinton, consisting of a flat thumb on a closed hand. It's neither a fist, nor a pointed finger, nor a thumbs-up. It's all of these and more, and is the best way to convey the message "I want to be forceful without looking like I'm threatening you."
The politician's advisers told him that pointing his finger at the crowd made it look like he was accusing them of something. They recommended that he use a clinton thumb instead.
by Gmanchot January 24, 2012