Occasion is a special event or a specific time when something is possible or when something will happen.(noun)
An example of an occasion is a birthday.
See occasion in Webster's New World College Dictionary
Origin: ME occasioun < OFr < L occasio, accidental opportunity, fit time < occasus, pp. of occidere, to fall < ob- (see ob-) + cadere, to fall: see case
See occasion in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old French
Origin: , from Latin occāsiō, occāsiōn-
Origin: , from occāsus
Origin: , past participle of occidere, to fall
Origin: : ob-, down; see ob-
Origin: + cadere, to fall; see kad- in Indo-European roots.
Learn more about occasion