(1):
(n.) A hollow cut in anything; a nick; an indentation.
(2):
(n.) A narrow passage between two elevation; a deep, close pass; a defile; as, the notch of a mountain.
(3):
(v. t.) To cut or make notches in; to indent; also, to score by notches; as, to notch a stick.
(4):
(v. t.) To fit the notch of (an arrow) to the string.