Fifth month (3)
I believe the answer is:
may
'fifth month' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for may that I've seen before include "The Darling Buds of - (H. E. Bates)" , "Time" , "Hawthorn blossom" , "The merry merry month( 3)" , "maid" .)