Sem`i*di*am"e*ter (?), n. (Math.) Half of a diameter; a right line, or the length of a right line, drawn from the center of a circle, a sphere, or other curved figure, to its circumference or periphery; a radius.

Sem`i*di*am"e*ter (?), n. (Math.) Half of a diameter; a right line, or the length of a right line, drawn from the center of a circle, a sphere, or other curved figure, to its circumference or periphery; a radius.