(military) A narrow ditch or trench made from the foremost parallel toward the glacis or covert way of a besieged place by digging under cover of gabions, etc.

(transitive) To subvert by digging or wearing away; to mine; to undermine; to destroy the foundation of. / (transitive, military) To pierce with saps.

plural of sap

Third-person singular simple present indicative form of sap

present participle of sap

The act by which something is sapped or depleted. / The act of excavating trenches. / The act of being struck with a sap or club.

simple past tense and past participle of sap

(dated, military) a fascine about three feet long, used in sapping, to close the crevices between the gabions before the parapet is made.

A dull light green pigment prepared from the juice of the ripe berries of the Rhamnus cathartica, or buckthorn. It is used especially by water-color artists.

(botany) Any large fungus of the genus Polyporus.