Substitute1. (n.) One who, or that which, is substituted or put in the place of another; one who acts for another; that which stands in lieu of something else
2. (n.) a person who enlists for military service in the place of a conscript or drafted man.
3. (n.) To put in the place of another person or thing; to exchange.
Thesaurus Entries
additional, advocate, agent, alter ego, alternate, alternative, amicus curiae, analogy, another, attorney, backup, backup man, bit player, champion, change, change for, changeling, commute, comparison, compound for, copy, counterfeit, delegate, deputy, dernier ressort, displace, double, double for, dub in, dummy, equal, equivalent, ersatz, exchange, executive officer, expediency, expedient, exponent, extra, fake, FALSE, father figure, father image, figurant, figurante, figurehead, fill-in, ghost, ghostwriter, give place to, imitation, lieutenant, locum, locum tenens, make do with, make way for, makeshift, metaphor, metonymy, mock, mother figure, mother surrogate, mute, next best thing, offer in exchange, other, paranymph, personnel, phony, pinch, pinch hitter, pinch-hit for, pleader, procurator, provisional, proxy, put up with, recourse, redeem, refuge, relay, relief, relieve, replace, replacement, representative, reserve, reserves, resort, ring in, ringer, second, second in command, second string, secondary, sham, shift with, sign, simulated, spare, spares, spear-carrier, spurious, stand in for, stand-in, standby, stopgap, sub, substituent, substitute for, substitution, succedaneum, supe, super, supernumerary, superseder, supplant, supplanter, supplemental, supplementary, supply, support, supporting actor, supporting cast, surrogate, swap, switch, symbol, synecdoche, take in exchange, temporary, tentative, third string, token, trade, understudy, utility, utility man, utility player, vicar, vicar general, vicarious, vice, vice-president, vice-regent, vicegerent, walk-on, walking gentleman