Like most holidays and physicals (6)
I believe the answer is:
annual
(Other definitions for annual that I've seen before include "Plant; yearbook" , "Coming once a year" , "Occurring yearly" , "Book; occurring once a year" , "Twelve-monthly" .)
I believe the answer is:
annual
(Other definitions for annual that I've seen before include "Plant; yearbook" , "Coming once a year" , "Occurring yearly" , "Book; occurring once a year" , "Twelve-monthly" .)