Sap (?), n. [AS. saep; akin to OHG. saf, G. saft, Icel. safi; of uncertain origin; possibly akin to L. sapere to taste, to be wise, sapa must or new wine boiled thick. Cf. Sapid, Sapient.]
1.
The juice of plants of any kind, especially the ascending and descending juices or circulating fluid essential to nutrition.
⇒ The ascending is the crude sap, the assimilation of which takes place in the leaves, when it becomes the elaborated sap suited to the growth of the plant.
2.
The sapwood, or alburnum, of a tree.
3.
A simpleton; a saphead; a milksop.
[Slang]
Sap ball Bot., any large fungus of the genus Polyporus. See Polyporus. -- Sap green, a dull light green pigment prepared from the juice of the ripe berries of the Rhamnus catharticus, or buckthorn. It is used especially by water-color artists. -- Sap rot, the dry rot. See under Dry. -- Sap sucker Zool., any one of several species of small American woodpeckers of the genus Sphyrapicus, especially the yellow-bellied woodpecker (S. varius) of the Eastern United States. They are so named because they puncture the bark of trees and feed upon the sap. The name is loosely applied to other woodpeckers. -- Sap tube Bot., a vessel that conveys sap.
© Webster 1913.
Sap, v. t. [imp. & p. p. Saped (?); p. pr. & vb. n. Sapping.] [F. saper (cf. Sp. zapar, It. zapare), fr. sape a sort of scythe, LL. sappa a sort of mattock.]
1.
To subvert by digging or wearing away; to mine; to undermine; to destroy the foundation of.
Nor safe their dwellings were, for sapped by floods,
Their houses fell upon their household gods.
Dryden.
2. Mil.
To pierce with saps.
3.
To make unstable or infirm; to unsettle; to weaken.
Ring out the grief that saps the mind.
Tennyson.
© Webster 1913.
Sap (?), v. i.
To proceed by mining, or by secretly undermining; to execute saps.
W. P. Craighill.
Both assaults carried on by sapping.
Tatler.
© Webster 1913.
Sap, n. Mil.
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.
Sap fagot Mil., a fascine about three feet long, used in sapping, to close the crevices between the gabions before the parapet is made. -- Sap roller Mil., a large gabion, six or seven feet long, filled with fascines, which the sapper sometimes rolls along before him for protection from the fire of an enemy.
© Webster 1913.