Autumn World

In North America, autumn is usually considered to start with the September equinox. In traditional East Asian solar term, Autumn starts on or around 8 August and ends on about 7 November. In Ireland, the autumn months according to the national meteorological service, Met Éireann, are September, October and November. However, according to the Irish Calendar which is based on ancient Celtic traditions, autumn lasts throughout the months of August, September, and October, or possibly a few days later, depending on tradition. In Australia, autumn officially begins on 1 March and ends 31 May. The vast diversity of the ecological zones of the South American, African and Australian continents renders the rigid European, North Asian and North American seasonal calendar an imposed cultural concept rather than relevant to climactic conditions. The seasonal cycles as named and described by the various indigenous Aboriginal peoples of Australia differ substantially from one another according to their local geographical and ecological environment and are intricately dependent on local environmental events and resources.
Etymology
The word autumn comes from the Old French word autompne (automne in modern French), and was later normalised to the original Latin word autumnus. There are rare examples of its use as early as the 12th century, but it became common by the 16th century.