Vernal, aestival, autumnal or brumal? (8)

I believe the answer is:

seasonal

(Other definitions for seasonal that I've seen before include "Occurring at particular times of the year" , "Changing throughout the year" , "specifically for Christmas period, say" , "Relating to spring, summer etc." , "For a particular period" .)

I've seen this clue in The Guardian.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.