Obtained leave on Tuesday (3)
I believe the answer is:
got
'obtained' is the definition.
('get' can be a synonym of 'obtain')
'leave on tuesday' is the wordplay.
'leave' becomes 'go' (to go is to depart or leave).
'on' says to put letters next to each other (in a down clue, letters appear on others).
'tuesday' becomes 't'.
'go'+'t'='GOT'
(Other definitions for got that I've seen before include "came by" , "Acquired" , "Obtained" , "Caught" , "Received; understood" .)