advocate, agent, alter ego, alternate, alternative, amicus curiae, analogy, attorney, backup, backup man, champion, change, changeling, comparison, copy, counterfeit, deputy, double, dummy, equal, equivalent, ersatz, exchange, executive officer, exponent, fake, figurehead, fill-in, gate, ghost, ghostwriter, imitation, lieutenant, locum, locum tenens, makeshift, metaphor, metonymy, next best thing, paranymph, personnel, phony, pleader, procurator, proxy, relief, replacement, representative, reserves, ringer, second in command, second string, secondary, sign, spares, stand-in, sub, substituent, substitute, substitution, succedaneum, superseder, supplanter, surrogate, symbol, synecdoche, third string, token, understudy, utility man, utility player, vicar, vicar general, vice, vice-president, vice-regent, vicegerent

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