Definition:Time/Unit/Day

Definition
The day is a derived unit of time.

It is defined as being:
 * $60 \times 60 \times 24$ seconds

or:
 * $60 \times 24$ minutes

or:
 * $24$ hours.

Also defined as
Until 1967, when the second was redefined to be the SI base unit of time, the day was the fundamental unit of time.

It was defined as being the length of time it takes the Earth to rotate once on its axis relative to the sun.

Also known as
The day as defined here is also known as a solar day so as to distinguish it from the sidereal day.