To make a gash, or long, deep incision in; -- applied chiefly to incisions in flesh.

ETYM Latin incisio: cf. French incision. Related to Incise.
1. A depression scratched or carved into a surface; SYN. scratch, notch, prick, slit, dent.
2. The cutting of or into body tissues or organs (especially by a surgeon as part of an operation); SYN. section.

1. A concave shape in a surface or edge or coastline etc.; SYN. indenture.
2. The act of indenting.
3. The space left between the margin and the start of an indented line; SYN. indent, indenture.

ETYM Akin to nock; cf. od. nock, OSw. nocka. Related to Nick a notch.
(Irregular plural: notches).
1. A V-shaped indentation.
2. A small cut; SYN. nick, snick.

A point at which a significant change occurs