Bored denture set in, somehow (12)
I believe the answer is:
uninterested
'bored' is the definition.
(similar in meaning)
'denture set in somehow' is the wordplay.
'somehow' is an anagram indicator.
'denture'+'set'+'in'='denturesetin'
'denturesetin' with letters rearranged gives 'UNINTERESTED'.
(Other definitions for uninterested that I've seen before include "Not concerned" , "Apathetic" , "indifferent" , "Bored" .)