| substitute(noun, adjective, person, reserve, extra) |
| surrogate(noun, person, thing, agent, substitute) |
| alternate(noun, adjective, person, reserve, extra) |
| switch(noun, verb, change, talk, argument) |
| substitution(noun, change, return, talk, argument) |
| deputy(noun, adjective, reserve, agent, substitute) |
| exchange(noun, verb, talk, argument, trade) |
| proxy(noun, adjective, agent, substitute, representative) |
| stand-in(noun, adjective, person, cover, reserve) |
| alternative(noun, adjective, extra, substitute, alternate) |
| double(noun, adjective, reproduction, copy, spare) |
| replacing |
| understudy(noun, adjective, reserve, substitute, alternative) |
| change(noun, talk, argument, transfer, substitute) |
| relief(noun, reserve, substitute, alternate, stalwart) |
| successor(noun, cover, reserve, alternative, alternate) |
| fill-in(noun, adjective, person, informal, reserve) |
| backup(noun, adjective, reserve, extra, agent) |
| commutation(noun, change, talk, argument, transfer) |
| displacement(noun, substitution) |