The business to be done by a body (such as a legislature) on a particular day; an agenda. / The most significant aspect of something; what is necessary or appropriate.

formerly, a day of the week on which a household’s laundry would be washed and dried; traditionally a Monday in Britain

(idiomatic, abstractly) Healthy eating and living using traditional temperate-zone fresh foods.

(set phrase) At some unspecified time in the future. / At some unspecified time in the past. / Used other than figuratively or idiomatically: see one, day.

(historical) 6 June 1944, the date when the Allies invaded western Europe in World War II.

(figuratively) The date of any major event planned for the future.

(Christianity, Islam, Judaism) The Last Judgment, Final Judgment, final trial of all humankind, both the living and dead by God expected to take place at the end of the world, when each is rewarded or punished according to his or her merits.

(idiomatic) recently; lately; a few days ago.

(Philippines) the day before yesterday.

(Canada) A holiday, originally to give thanks to God for the harvest, celebrated annually on the second Monday of October.