1. (verb)substitute, deputize, deputise, step in act as a substitute Synonyms: depute, fill in, sub, exchange, intervene, step in, interpose, deputise, stand in, interfere, replace, deputize, interchange, substitute
2. (verb)depute, deputize, deputise appoint as a substitute Synonyms: depute, assign, delegate, deputize, step in, deputise, designate, substitute