notch

A small cut.

The location in a range of mountains of a geological formation that is lower than the surrounding peaks.

A V-shaped indentation.

“mandibular notch”

A V-shaped or U-shaped indentation carved or scratched into a surface.

“there were four notches in the handle of his revolver”

Cut or make a notch into.

“notch the rope”

Notch a surface to record something.