profiteer v.

mid-13c., "income derived from an office, property, transaction, etc.;" c. 1300, "benefit, spiritual benefit, advantage;" from Old French prufit, porfit "profit, gain" (mid-12c.), from Latin profectus "growth, advance, increase, success, progress," noun use of past participle of proficere "accomplish, make progress; be useful, do good; have success, profit," from pro "forward" (from PIE root *per- (1) "forward") + combining form of facere "to make, do" (from PIE root *dhe- "to set, put"). An Old English word "gain, profit" was gewinn.

From mid-14c. as "use, usefulness." The specific sense of "the advantage or gain resulting to the owner of capita; from its employment in any undertaking, acquisition beyond expenditure" is from c. 1600. Profit margin "what remains when costs involved are deducted from profit" is attested from 1853. Profit-sharing is by 1881.

As used in political economy, profit means what is left of the product of industry after deducting the wages, the price of raw materials, and the rent paid in the production, and is considered as being composed of three parts — interest, risk or insurance, and wages of superintendence. [Century Dictionary]

noun word-forming element meaning "one who" (operates, produces, deals in); Englished form of French -ier, from Latin -arius, -iarius; compare -ary. Usually in English words of more recent borrowing from French; older words tend to keep -ier.