Definition of "Occasion" :

noun: an event that occurs at a critical time

"It was needed only on special occasions."

noun: a vaguely specified social event

"An occasion arranged to honor the president."

noun: reason

"There was no occasion for complaint."

noun: an opportunity to do something

"There was never an occasion for her to demonstrate her skill."

noun: the time of a particular event

"On the occasion of his 60th birthday."

verb: give occasion to