Loud like Parker, initially ignored in the centre (5)
I believe the answer is:
noisy
'loud' is the definition.
('noisy' is associated in meaning with 'loud')
'like parker initially ignored in the centre' is the wordplay.
'like parker' becomes 'nosy' (reference to the phrase Nosy Parker).
'initially' suggests taking the first letters.
'in the centre' means one lot of letters goes inside another (some letters go in the middle of other letters).
The first letter of 'ignored' is 'i'.
'nosy' placed around 'i' is 'NOISY'.
(Other definitions for noisy that I've seen before include "Making much sound" , "Vociferous" , "Raucous" , "Vocal" , "Disturbingly loud" .)