day

Any period of 24 hours.

“I've been here for two days and a bit.”

A period from midnight to the following midnight.

“The day begins at midnight.”

Rotational period of a planet (especially Earth).

“A day on Mars is slightly over 24 hours.”

The part of a day period which one spends at one’s job, school, etc.

“I worked two days last week.”

Part of a day period between sunrise and sunset where one enjoys daylight; daytime.

“day and night;  I work at night and sleep during the day.”

A specified time or period; time, considered with reference to the existence or prominence of a person or thing; age; time.

“Every dog has its day.”

A period of contention of a day or less.

“The day belonged to the Allies.”

A 24-hour period beginning at 6am or sunrise.

“Your 8am forecast: The high for the day will be 30 and the low, before dawn, will be 10.”

To spend a day (in a place).