Procoelian \Pro*c[oe]"li*an\, a. [See {Proc[oe]le}.] (Anat & Zo["o]l.) Concave in front; as, proc[oe]lian vertebr[ae], which have the anterior end of the centra concave and the posterior convex. Procoelian \Pro*c[oe]"li*an\, n. (Zo["o]l.) A reptile having proc[oe]lian vertebr[ae]; one of the Proc[oe]lia.