Exploit, n.
Etymology: [OE. esploit success, OF. esploit, espleit,revenue, product, vigor, force, exploit, F. exploit exploit, fr. L. explicitum, prop. p.p. neut. of explicare to unfold, display, exhibit; ex+plicare to fold. See Ply, and cf. Explicit, Explicate.]
1. A deed or act; especially, a heroic act; a deed of renown; an adventurous or noble achievement; as, the exploits of Alexander the Great. Ripe for exploits and mighty enterprises. Shak.
2. Combat; war. [Obs.] He made haste to exploit some warlike service. Holland.
2. Etym: [F. exploiter.]
To utilize; to make available; to get the value or usefulness out of; as, to exploit a mine or agricultural lands; to exploit public opinion. [Recent]
1 more senses
3. Hence: To draw an illegitimate profit from; to speculate on; to put upon. [Recent] In no sense whatever does a man who accumulates a fortune by legitimate industry exploit his employés or make his capital "out of" anybody else. W. G. Sumner.
Shades of meaning
Fernald has no entry of its own for exploit; he lists it under act.
Where he writes about it:
As between act and deed, deed is commonly used of great, notable, and impressive acts, as are achievement, exploit, and feat. — from act
An exploit is a conspicuous or glorious deed, involving valor or heroism, usually combined with strength, skill, loftiness of thought, and readiness of resource; an achievement is the doing of something great and noteworthy; an exploit is brilliant, but its effect may be transient; an achievement is solid, and its effect enduring. — from act