hiddenmark
nounUK /ˈhɪdən mɑːk/
US /ˈhɪdən mɑːrk/
A hidden mark is a tiny sign you cannot see easily.
The treasure map had a hidden mark that only showed under a special light.
OTHER MEANINGS
2. A secret symbol used to prove who made something.
The artist put a hidden mark on the back of the painting.
3. A small spot that is hard to notice on a surface.
There was a hidden mark on the glass that you could only see from the side.
4. A private note or signal meant for only one person.
She left a hidden mark in the book to show her friend which page to read.