Shortest month (8)
I believe the answer is:
february
'shortest month' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for february that I've seen before include "Month of Lincoln's, Washington's birthdays" , "a few weeks" , "In wintertime" , "Month named for Roman festival of purification" , "Period of 28 or 29 days?" .)