Present on Tuesday, but not here (5)
I believe the answer is:
there
'not here' is the definition.
('there' is the opposite to 'here')
'present on tuesday' is the wordplay.
'present' becomes 'here' (both can mean in attendance).
'on' is a charade indicator (letters next to each other).
'tuesday' becomes 't'.
'here' after 't' is 'THERE'.
'but' acts as a link.
(Other definitions for there that I've seen before include "Word of comfort" , "In that location" , "Expression of comfort" , "It's said to comfort" , "it may be said to be comforting" .)