circĭnātĭo

ōnis, f.

circino

I. the circumference of a circle, a circle (a word of Vitr.): linea circinationis, Vitr. 1, 6, 6: circuli, id. 9, 7, 2; 3, 3; 10, 10 al.—Of the circular path of the planets, Vitr. 9, 4, pp. 264, 266 Bip.
Lewis & Short
A Latin Dictionary, 1879
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