Short day for getting married (3)
I believe the answer is:
wed
I believe this clue is a double definition.
'short day' is the first definition.
(abbreviation for Wednesday; 'short' indicates a short form)
'married' is the second definition.
(wed can mean married)
'for getting' acts as a link.
(Other definitions for wed that I've seen before include "united" , "Joined in the dew" , "Espouse" , "Join" , "Take in marriage" .)