One of the divisions of the year, marked by alternations in
   the length of day and night, or by distinct conditions of temperature,
   moisture, etc., caused mainly by the relative position of the earth
   with respect to the sun. In the north temperate zone, four seasons,
   namely, spring, summer, autumn, and winter, are generally recognized.
   Some parts of the world have three seasons, -- the dry, the rainy, and
   the cold; other parts have but two, -- the dry and the rainy.