Keep secret visit short, previously being drunk (7)
I believe the answer is:
conceal
'keep secret' is the definition.
(I've seen this in another clue)
'visit short previously being drunk' is the wordplay.
'visit short' becomes 'cal' (I can't justify this - if you can you should believe this answer much more).
'previously' becomes 'once' (once means in the past).
'being drunk' means one lot of letters goes inside another (inserted letters are drunk in).
'cal' placed around 'once' is 'CONCEAL'.
Can you help me to learn more?
(Other definitions for conceal that I've seen before include "Screen" , "Hide, cover" , "hush up!" , "Keep out of sight" , "'Hide, keep secret (7)'" .)