Definition of day (noun)
- time for Earth to make a complete rotation on its axis
- some point or period in time
- "it should arrive any day now"; "after that day she never trusted him again"; "those were the days"; "these days it is not unusual"
- a day assigned to a particular purpose or observance
- "Mother's Day"
- the time after sunrise and before sunset while it is light outside
- the recurring hours when you are not sleeping (especially those when you are working)
- "my day began early this morning"; "it was a busy day on the stock exchange"; "she called it a day and went to bed"
- an era of existence or influence
- "in the day of the dinosaurs"; "in the days of the Roman Empire"; "in the days of sailing ships"; "he was a successful pianist in his day"
- the period of time taken by a particular planet (e.g. Mars) to make a complete rotation on its axis
- "how long is a day on Jupiter?"
- the time for one complete rotation of the earth relative to a particular star, about 4 minutes shorter than a mean solar day
- synonyms: sidereal day
- a period of opportunity
- "he deserves his day in court"; "every dog has his day"
- United States writer best known for his autobiographical works (1874-1935)
Source: Princeton University Wordnet