A long, narrow ditch in the earth; an open ditch for draining.

沟；沟渠。

A deep ditch dug in a zone of battle and held as a defensive position or as a base from which to attack.

【军】壕沟。

To cut a ditch in.

掘沟。

To entrench, as an army.

掘战壕(如军队)。

To encroach.

侵入。