Work bishop gets around Slough (3)
I believe the answer is:
bog
'slough' is the definition.
(both can mean a swampy area)
'work bishop gets around' is the wordplay.
'work' becomes 'go' (synonyms).
'bishop' becomes 'B' (abbreviation for bishop in chess).
'gets around' shows that the letters should be reversed in order (I've seen 'get around' mean this).
'go'+'b'='gob'
'gob' in reverse letter order is 'BOG'.
(Other definitions for bog that I've seen before include "Soft muddy area" , "Quagmire" , "Marsh" , "Slough" , "Mire" .)