noun🔗Share立体弧度，球面度 In the International System of Units, the derived unit of solid angle; the solid angle subtended at the centre of a sphere of radius r by a portion of the surface of the sphere that has area r2. Symbol: sr"The lamp's reflector concentrates the light into a solid angle of approximately one steradian, providing focused illumination. "这盏灯的反射器将光线集中在一个大约一个球面度 (lì tǐ hú dù) 的立体角内，从而提供集中的照明。mathphysicsunitChat with AIVocabulary GamePractice Reading
