The definition of a day is a 24-hour period of time or the period of light between sunrise and sunset.(noun)
See day in Webster's New World College Dictionary
Origin: ME dai < OE dæg (pl. dagas), akin to ON dagr, Goth dags, OHG tag < PGmc *dagwaz, prob. < IE base *ahes, day, with d- by assoc. with base *dhegwh-, to burn
See day in American Heritage Dictionary 4
Origin: Middle English dai, day
Origin: , from Old English dǽg; see agh- in Indo-European roots.
, Clarence Shepard, Jr. 1874-1935.
, Dorothy 1897-1980.
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