Worker in modest shed (6)
I believe the answer is:
shanty
'shed' is the definition.
(thesaurus)
'worker in modest' is the wordplay.
'worker' becomes 'ant' (worker is a type of ant).
'in' indicates putting letters inside.
'modest' becomes 'shy'.
'ant' placed within 'shy' is 'SHANTY'.
(Other definitions for shanty that I've seen before include "Here you get inferior accommodation" , "Roughly built hut" , "Number at sea" , "Sea song; crude shack" , "low abode" .)