Writer in centre set off siren (7)
I believe the answer is:
enticer
'siren' is the definition.
(thesaurus)
'writer in centre set off' is the wordplay.
'writer' becomes 'i' (the person who is writing these clues).
'in' indicates putting letters inside.
'set off' indicates an anagram.
'centre' is an anagram of 'entcer'.
'i' put within 'entcer' is 'ENTICER'.
(Other definitions for enticer that I've seen before include "temptress?" , "Who offers temptation" .)