Rotten to get place free (6)
I believe the answer is:
putrid
'rotten' is the definition.
(synonyms)
'get place free' is the wordplay.
'get' says to put letters next to each other.
'place' becomes 'put' (synonyms).
'free' becomes 'rid' (to be free of something is to be rid of it).
'put' put next to 'rid' is 'PUTRID'.
'to' acts as a link.
(Other definitions for putrid that I've seen before include "Decomposing and fetid" , "Rancid" , "corrupt" , "Bad smelling, rotting" , "contaminated" .)