ETYM Old Eng. forow, forgh, furgh, AS. furh.
A long shallow trench in the ground (especially one made by a plow).

ETYM Dutch groef, groeve; akin to Eng. grove. Related to Grove.
1. A long narrow furrow or channel cut by a natural process (such as erosion) or by a tool (as e.g. a groove in a phonograph record).
2. (Anatomy) Any furrow or channel on a bodily structure or part.

ETYM Old Eng. gotere, Old Fren. goutiere, French gouttičre, from Old Fren. gote, goute, drop, French goutte, from Latin gutta.
A channel along the eaves or on the roof; collects and carries away rainwater; SYN. trough.

Mortise.

ETYM French mortaise; cf. Spanish mortaja, Arabic murtazz fixed, or W. mortais, Irish mortis, moirtis, Gael. moirteis.
A square hole made to receive a tenon and so to form a joint; SYN. mortice.
Hole or recess made in wood to receive a tenon.

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.