Lewis & Short

circĭno, āvi, ātum, 1, v. a. [circinus], to make round, to round (perh. not anteAug.): arbores, quae in orbem ramos circinant, Plin. 17, 12, 17, § 88; 16, 38, 73, § 185: circinatum tympanum, id. 18, 34, 77, § 332: folia circinatae rotunditatis, id. 16, 23, 35, § 86
Poet.: (Cyllenius) inclinat cursus, et easdem circinat auras, flies through in a circular course, * Ov. M. 2, 721: utque suos arcus per nubila circinat Iris, vaults, arches, Manil. 1, 710.