Second Unit of Plane Angle

**Semantic type:** Quantitative Concept

**Definition:** A unit of angular measure equal to 1/60 arcminute or to 1/360 degree. Second is also called the arcsecond to distinguish it from the second of time. There are 1296000 seconds in a circle. The international standard ISO 31 recommends that angles be stated in degrees and decimal fractions of the degree, without use of arcminutes and arcseconds.

**Synonyms:** - " - '' - Arcsecond - Second - second - second