Thumbknuck 

To briskly insert thumb, up to the knuckle, into rectum without warning.

Hey man, she looks pretty kinky, I’d totally thumbknuck her!

Thumbknuck by Squaidgiver336 September 29, 2019

thumbfucked 

To get a thumbs down vote on urban dictionary.

Someone just thumbfucked me on urban dictionary.

thumbfucked by jpg3 July 17, 2011

Thumbsucker

An adult who whines about very trivial things. Making them appear childish.

A woman sitting at a traffic light, behind a car displaying a non-Christian Evolve Fish emblem, yelled unchristian obscenities to the driver.
The passenger in the car next to her rolled down his window, and calmly asked? "Do you realize how childish your behaving?"
At this she screamed more angry obscenities.
The passenger calmly waited for her to calm down, and as if speaking to a child, said. "Where's your mommy? Thumbsucker."

Thumbsucker by Chat Noir May 24, 2008

thumbfuck 

to insert ones thumb into the anal or vaginal orfice.

i said "thumbfuck", you dumbfuck!

thumbfuck by dj jazzy jeff and the fresh prints January 21, 2004

thumbfucking my phone 

The hateful practice of text messaging.

I mean, I like the girl, but she's always got me thumbfucking my phone.

thumbfucking my phone by Jan Warren February 5, 2008

Thumbsucker

An immature person.

Donald Trump is a thumbsucker.

Thumbsucker by TRAVVIS December 29, 2017

Thumbfucker

A thumbfucker is a person who is constantly texting on their cell phone.

David called Phillip a thumbfucker as he drove by watching Phillip text on his phone.

Thumbfucker by Cagney February 24, 2010