Fellow, one left being given time inside, shown to be this? (6)
I believe the answer is:
guilty
'fellow' is the definition.
Both the answer and definition are adjectives. Maybe you can see a link between them that I don't see?
'one left being given time inside shown to be this?' is the wordplay.
I cannot quite understand how this works, but
'one' could be 'i' (Roman numeral) and 'i' is located in the answer.
'left' could be 'l' (common abbreviation) and 'l' is located in the answer.
'time' could be 't' (abbreviation) and 't' is located in the answer.
'being' could be 'guy' (guy is a kind of being) and 'guy' is present in the leftover letters.
No letters remain.
This explanation may well be incorrect...
(Other definitions for guilty that I've seen before include "Jury verdict - the accused did it" , "Having done wrong - a plea in court" , "Justly charged" , "(Found) responsible for offence" , "Blameworthy, at fault" .)