radian   (TTS Sound)

The radian has 1 Senses.

• radian, rad
• ラジアン
• the unit of plane angle adopted under the Systeme International d'Unites; equal to the angle at the center of a circle subtended by an arc equal in length to the radius (approximately 57.295 degrees)
• 国際単位系で採用されている平面角の単位