Another chained monster (7)
I believe the answer is:
echidna
'monster' is the definition.
(thesaurus)
'another chained' is the wordplay.
'another' indicates an anagram.
'chained' with letters rearranged gives 'ECHIDNA'.
(Other definitions for echidna that I've seen before include "Had nice (anag) -- spiny anteater" , "Spiny creature" , "Creature with spines" , "Australian creature" , "This insectivore" .)