Definition from Wiktionary, the free dictionary
See also radián
From radi(us) + -an
- (geometry) In the International System of Units, the derived unit of plane angular measure of angle equal to the angle subtended at the centre of a circle by an arc of its circumference equal in length to the radius of the circle. Symbol: rad
Derived terms 
See also 
Audio (Paris) (file)
radian m (plural radians)
declension of radian
radian (infinitive radiar)
- Second-person plural (ustedes) present indicative form of radiar.
- Third-person plural (ellos, ellas, also used with ustedes?) present indicative form of radiar.
- a radian, an angular measure where pi radians = 180°
Declension of radian