Autumn, also known as fall in North American English, [1] is one of the four temperate seasons on Earth. Outside the tropics, autumn marks the transition from summer to winter, beginning in September (Northern Hemisphere) or March (Southern Hemisphere).
autumn, season of the year between summer and winter during which temperatures gradually decrease. It is often called fall in the United States because leaves fall from the trees at that time.
Autumn, also called fall, is the transitional season between summer and winter, marked by cooler temperatures, shorter days, and leaves changing color and falling.