Open at the above time (5)
I believe the answer is:
overt
'open' is the definition.
('overt' is associated in meaning with 'open')
'at the above time' is the wordplay.
'at' is a charade indicator (letters next to each other).
'the above' becomes 'over' (I've seen this before).
'time' becomes 't'.
'over' put next to 't' is 'OVERT'.
(Other definitions for overt that I've seen before include "Done or shown openly" , "Conspicuous" , "Open and obvious" , "Clear" , "Done in an obvious way" .)