Dry in half a jiffy (3)
I believe the answer is:
sec
This clue is a double definition.
'dry' is the first definition.
(similar in meaning)
'half a jiffy' is the second definition.
(thesaurus)
'in' is the link.
(Other definitions for sec that I've seen before include "sparkling?" , "'Dry, as wine (3)'" , "(Of wines) dry" , "Dry wine perhaps" , "sort of function" .)