Definitions of notch:

• noun:   a small cut
• noun:   a V-shaped or U-shaped indentation carved or scratched into a surface

  Example: "There were four notches in the handle of his revolver"

• noun:   a V-shaped indentation

  Example: "Mandibular notch"

• noun:   the location in a range of mountains of a geological formation that is lower than the surrounding peaks
• verb:   notch a surface to record something
• verb:   cut or make a notch into

  Example: "Notch the rope"

• name:  A surname (very rare: popularity rank in the U.S.: #69588)