Motion perhaps damaged a tree -- leap out! (4,8)
I believe the answer is:
poet laureate
'motion perhaps' is the definition.
(I know that Andrew Motion was a poet laureate)
'damaged a tree leap out' is the wordplay.
'damaged' indicates anagramming the letters.
'a'+'tree'+'leap'+'out'='atreeleapout'
'atreeleapout' is an anagram of 'POET LAUREATE'.
(Other definitions for poet laureate that I've seen before include "Official versifier" , "such as Tennyson" , "Court versifier" , "Queen picked out" , "Motion, at present" .)