Biol. Also (in Dicts.) symbion. [irreg. f. Gr. συμβιῶν, pr. pple. of συμβιοῦν: see next.] Either of two organisms living in symbiosis; a commensal.
1887. Garnsey & Balfour, trans. De Bary’s Fungi, 360. The resulis of the reciprocal action of the two symbionts.
1902. H. M. Coulter, Plant Studies, 162. In symbiosis one of the symbionts may be an animal.
