The lack of exercise caused by being on a portable game device or smart phone for extended periods of time. Typically Apple or Blackberry users
by Cyberwulf July 18, 2012

Book thumb is from holding open a book with your thumb and index finger for long periods of time, causing pain in your thumb muscle.
by blueberrypancak September 2, 2013

A cup in which you put your thumbs in cold water after burning them on a hot bowl of ramen noodles after putting them in the boiling water.
by Picodegio December 28, 2017

When youtubers use a picture of boobs as their thumbnail to attract perverted viewers to their videos and increase the number of views they get
by phillipm August 23, 2014

To text for the purpose of social communication; from schmooze, Yiddish meaning to chat, to have an informal conversation; "thumb" is a reference to the use of thumbs to text on a mobile phone
I'll be in meetings all week, but we'll thumb-schmooze every day until we can get together on the weekend.
by Liz141 April 21, 2017

Thumb licker: (noun) a person who puts both of their thumbs in their own mouth then shoves them up their partners,friends, peers, ect. asshole then licks their thumbs again.
by Thumblicker23 November 12, 2017
