1. Canada season after summer and before winter: the season occurring between summer and winter. Autumn traditionally lasts from September 22 to December 21 in the northern hemisphere, and from March 21 to June 21 in the southern hemisphere. U.S. term fall
2. time of late maturity: a time in the development of something that follows its most vigorous and successful phase, before its decline in the autumn of his career as a cellist
