Contemptible centre of operations (4)
I believe the answer is:
base
This clue is a double definition.
'contemptible' is the first definition.
(synonyms)
'centre of operations' is the second definition.
(I've seen this before)
(Other definitions for base that I've seen before include "Not worth much" , "centre from which soldiers operate" , "Shameful - headquarters" , "Lowest part of something" , "'Foundation, bottom (4)'" .)