HEAD n. 2 definitions
The uppermost, foremost, or most important part of an inanimate object; such a part as may be considered to resemble the head of an animal; often, also, the larger, thicker, or heavier part or extremity, in distinction from the smaller or thinner part, or from the point or edge; as, the head of a cane, a nail, a spear,…
SAP n.
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 ga…