Computer expert almost stylish in support (6)
I believe the answer is:
techie
'computer expert' is the definition.
(I've seen this before)
'almost stylish in support' is the wordplay.
'almost' means to remove the last letter (most of the word but not all of it).
'stylish' becomes 'chic' (similar in meaning).
'in' is an insertion indicator.
'support' becomes 'tee' (tee is a kind of support).
'chic' with its last letter taken off is 'chi'.
'chi' inserted within 'tee' is 'TECHIE'.
(Other definitions for techie that I've seen before include "IT whizz" , "Expert in some practical science" , "computer expert" , "PC expert" .)