- day [dā]n.[ME dai < OE dæg (pl. dagas), akin to ON dagr, Goth dags, OHG tag < PGmc * dagwaz, prob. < IE base * ag̑hes, day, with d- by assoc. with base * dhegwh-, to burn]1.a) the period of light between sunrise and sunsetb) daylightc) sunshine2.a) the 24-hour period (mean solar day) that it takes the earth to rotate once on its axis with respect to the sun: the civil or legal day is from midnight to midnight, the astronomical day from noon to noon: see SIDEREAL DAYb) Astron. the time that it takes any celestial body to revolve once on its axis3. [often D-] a particular or specified day [Memorial Day]4. [also pl.] a period or time; era; age [the best writer of her day, in days of old]5. a time of flourishing, power, glory, success, etc. [he has had his day]6. the struggle or contest occurring on a certain day [they won the day]7. the time one works each day [an eight-hour day]8. an unspecified past or future time [one of these days]9. [pl.] one's lifetime; life [to spend one's days in study]——————call it a dayInformal to stop whatever one is engaged in, as work——————day after dayevery day or for many successive days——————day by dayeach day——————day in, day outevery day——————from day to day1. from one day to the next2. without particular concern about the future
English World dictionary. V. Neufeldt. 2014.