Occasion for draftees, occasionally (4)
I believe the answer is:
date
'occasion' is the definition.
Although both the answer and definition are singular nouns, I don't see how one could define the other.
'draftees occasionally' is the wordplay.
'occasionally' indicates alternate letters (letters taken at regular intervals or occasions).
The alternate letters of 'draftees' are 'DATE'.
'for' is the link.
Can you help me to learn more?
(Other definitions for date that I've seen before include "Estimate age of" , "to take out" , "6 [TREE]" , "Court" , "Day, month and year" .)