Lamb with poetic bent in tune (10)
I believe the answer is:
compatible
'in tune' is the definition.
(thesaurus)
'lamb with poetic bent' is the wordplay.
'with' says to put letters next to each other.
'bent' is an anagram indicator.
'lamb'+'poetic'='lambpoetic'
'lambpoetic' is an anagram of 'COMPATIBLE'.
(Other definitions for compatible that I've seen before include "in harmony" , "Able to coexist happily" , "Well suited" .)