Zool. [ad. Gr. τρίοδος a place where three ways meet, f. τρι-, TRI- + ὁδός way.] Name for a simple triradiate sponge-spicule, consisting of three rays inclined at angles of 120°.
1887. Sollas, in Encycl. Brit., XXII. 416/2. Fig. 12 … c, triod (triaxon triactine).
