1 definition by Samqwell
Shark Thumb.
The sexual act of placing you little finger (pinky) inside your partners anus (butt), while keeping all other fingers tucked in except the thumb that will stand proud and looks like a shark fin just slightly cresting the bottom of your partners posterior (butt) as they lay on their front.
The sexual act of placing you little finger (pinky) inside your partners anus (butt), while keeping all other fingers tucked in except the thumb that will stand proud and looks like a shark fin just slightly cresting the bottom of your partners posterior (butt) as they lay on their front.
During foreplay Sam Shark Thumb'ed meredith last night, meredith giggled as she looked over her shoulder and saw the shark fin (Sam's thumb).
by Samqwell December 31, 2020