Philosopher with unusually deep pockets I bug (9)
I believe the answer is:
millipede
'bug' is the definition.
(I've seen this before)
'philosopher with unusually deep pockets i' is the wordplay.
'philosopher' becomes 'mill' (John Stuart Mill).
'with' is a charade indicator (letters next to each other).
'unusually' indicates anagramming the letters.
'pockets' is an insertion indicator.
'deep' with letters rearranged gives 'pede'.
'pede' placed around 'i' is 'ipede'.
'mill'+'ipede'='MILLIPEDE'
(Other definitions for millipede that I've seen before include "Many-legged creature" , "Bug" .)