Shortly ducks are seen in opposite directions (4)
I believe the answer is:
soon
'shortly' is the definition.
('soon' can be a synonym of 'shortly')
'ducks are seen in opposite directions' is the wordplay.
'ducks' becomes 'oo' (I've seen this in other clues).
'are seen in' indicates putting letters inside.
'opposite directions' becomes 'sn' (opposite compass points**).
'oo' going within 'sn' is 'SOON'.
(Other definitions for soon that I've seen before include "Before long" , "in a minute" , "In the near future" , "Shortly" , "In a little while" .)