n. [ L. centrum + -oid. ] The center of mass, inertia, or gravity of a body or system of bodies. [ 1913 Webster ]
a. [ Gr. &unr_; a cover + &unr_; a prickle + -oid. ] (Zool.) Pertaining to the Pomacentridæ, a family of bright-colored tropical fishes having spiny opercula; -- often called coral fishes. [ 1913 Webster ]