Temporary work in the theatre (6)
I believe the answer is:
acting
This clue is a triple definition!
'temporary' is the first definition.
(similar in meaning)
'work' is the second definition.
(thesaurus)
'in the theatre' is the third definition.
(I've seen this before)
(Other definitions for acting that I've seen before include "Behaving like a player" , "Feigning" , "Temporary - work in the theatre" , "Deputy" , "Behaving like thespian" .)