Past, present and future (6)
I believe the answer is:
tenses
'past present and future' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for tenses that I've seen before include "Tautens; verb forms" , "Becomes stretched or taut" , "Verb forms that indicate time" , "Verb forms indicating time" , "Future or past, say" .)