orbĭcŭlus

I. a small disk; a sheave, roller, pulley, etc. (anteclass. and post-Aug.), Cato, R. R. 3, 6; 22, 2; Col. 4, 30, 4; Vitr. 10, 5: radix concisa in orbiculos, cut in little disks or slices, Plin. 25, 13, 94, § 148; Inscr. Orell. 2519.— Esp., Vitr. 10, 2, 9.