SAP

I. noun Etymology: Middle English, from Old English sæp; akin to Old High German saf ~ Date: before 12th century 1. the fluid part of a plant, b. a body fluid (as blood) essential to life, health, or vigor, bodily health and vigor, a foolish gullible person, blackjack , bludgeon , ~less adjective ~lessness noun II. transitive verb (~ped; ~ping) Date: 1725 to drain or deprive of ~, to knock out with a ~, III. verb (~ped; ~ping) Etymology: Middle French ~per, from Old Italian zappare, from zappa hoe Date: 1598 intransitive verb to proceed by digging a ~, transitive verb to subvert by digging or eroding the substratum or foundation ; undermine , 2. to gradually diminish the supply or intensity of , to weaken or exhaust the energy or vitality of , to operate against or pierce by a ~, see: weaken IV. noun Etymology: French ~e, from ~er Date: 1642 the extension of a trench to a point beneath an enemy's fortifications