/ ˈɔːtəm; NAmE / ( especially BrE ) ( NAmE usually fall ) noun
[ U , C ] the season of the year between summer and winter, when leaves change colour and the weather becomes colder :
in the autumn of 2004
in early / late autumn
the autumn term (= for example at a school or college in Britain)
autumn colours / leaves
It's been a very mild autumn this year.
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WORD ORIGIN
late Middle English : from Old French autompne , or later directly from Latin autumnus .