# Minute

This article is about the unit of time. For angle and right ascension, see Minute and second of arc. For the written record of a meeting, see Minutes. For other uses of the word, see Minute (disambiguation).

The minute is a unit of time or of angle. As a unit of time, the minute is equal to 160 (the first sexagesimal fraction[1]) of an hour, or 60 seconds. In the UTC time standard, a minute on rare occasions has 61 seconds, a consequence of leap seconds (there is a provision to insert a negative leap second, which would result in a 59-second minute, but this has never happened in more than 40 years under this system). As a unit of angle, the minute of arc is equal to 160 of a degree, or 60 seconds (of arc). Although not an SI unit for either time or angle, the minute is accepted for use with SI units for both.[2] The SI symbols for minute or minutes are min for time measurement, and the prime symbol after a number, e.g. 5, for angle measurement. The prime is also sometimes used informally to denote minutes of time.

In contrast to the hour, the minute (and the second) does not have a clear historical background. What is traceable only is that it started being recorded in the Middle Ages due to the ability of construction of "precision" timepieces (mechanical and water clocks). However, no consistent records of the origin for the division as 160 part of the hour (and the second 160 of the minute) have ever been found, despite many speculations.

Historically, the word "minute" comes from the Latin pars minuta prima, meaning "first small part". This division of the hour can be further refined with a "second small part" (Latin: pars minuta secunda), and this is where the word "second" comes from. For even further refinement, the term "third" (160 of a second) remains in some languages, for example Polish (tercja) and Turkish (salise), although most modern usage subdivides seconds by using decimals. The symbol notation of the prime for minutes and double prime for seconds can be seen as indicating the first and second cut of the hour (similar to how the foot is the first cut of the yard or perhaps chain, with inches as the second cut). In 1267, the medieval scientist Roger Bacon, writing in Latin, defined the division of time between full moons as a number of hours, minutes, seconds, thirds, and fourths (horae, minuta, secunda, tertia, and quarta) after noon on specified calendar dates.[3]

## Notes and references

1. "What is the origin of hours, minutes and seconds?". Wisteme. Archived from the original on 24 March 2012. Retrieved 2011-05-25. What we now call a minute derives from the first fractional sexagesimal place.
2. "Non-SI units accepted for use with the SI, and units based on fundamental constants". Bureau International de Poids et Mesures. Retrieved 2011-05-25.
3. R Bacon (2000) [1928]. The Opus Majus of Roger Bacon. BR Belle. University of Pennsylvania Press. table facing page 231. ISBN 978-1-85506-856-8.