| substitution(noun, replacement) |
| acting(adjective, present, short, limited, brief) |
| appointee(noun, agent, deputy) |
| backup man(noun, expression, idiom) |
| fill in(verb, expression, phrasal verb, change, cover) |
| go-between(noun, agent, representative, operative, manager) |
| intermediary(noun, agent, representative, operative, manager) |
| locum(noun, replacement, alternative, someone, something) |
| other(noun, adjective, extra, replacement, alternative) |
| reliever |
| ringer(noun, model, deputy, mannequin) |
| secondary(reserve, subsidiary, deputy, supportive) |
| spokesman(noun, deputy, communicator) |
| stand in for(verb, expression, idiom, phrasal verb, mean) |
| successor(noun, cover, reserve, alternative, someone) |
| supplemental(adjective, extra, alternative, auxiliary, supernumerary) |
| supplementary(adjective, extra, alternative, auxiliary, supernumerary) |
| vicarious(adjective, extra, alternative, auxiliary, supernumerary) |
| succedaneum(noun, replacement, alternative, someone, something) |
| additional(adjective, extra, alternative, auxiliary, supernumerary) |