thumbmark
/ˈθʌmbmɑrk/Definitions
1. noun
A mark or impression made on the skin by the tip of the thumb, typically after pinching the skin between the thumb and another finger.
“The child’s thumbmark on her arm was a sign of her curiosity about the sharp object.”
2. verb
To mark or leave an impression on the skin, typically with the tip of the thumb.
“The toddler thumbmarked the soft toy with her curious fingers.”