Irrelevant fellow? (8)
I believe the answer is:
academic
This clue is a double definition.
'irrelevant' is the first definition.
(I've seen this before)
'fellow?' is the second definition.
(I've seen this before)
(Other definitions for academic that I've seen before include "Scholarly: hypothetical" , "Scholarly as opposed to practical (8)" , "Unimportant" , "Donnish" , "of educational kind" .)