thumb
1. thumb \'th*m\ n [ME thoume, thoumbe, fr. OE thu-ma; akin to OHG thu-]mo thumb, L tume-re to swell, Gk so-s safe, whole 1: the first digit of the human hand opposable to the other fingers; als o : the corresponding digit in lower animals 2: the part of a glove or mitten that covers the thumb 3: a convex molding : OVOLO 2. thumb vt 1a: to leaf through (pages) with the thumb : TURN 1b: to soil or wear by or as if by repeated thumbing 2: to request or obtain (a ride) in a passing automobile by signaling with the thumb : to place the thumb at one's nose and extend the fingers as a gesture of scorn or defiance - thumb one's nose
Webster's English Dictionary