symbiont

1. (ecology) An organism that lives in a symbiotic relationship.Examples: "The close analogies between DNA-containing eukaryotic cell organelles and microbial symbionts require revision of classic cell theory, wrote Scwemmler and Schenk (1980) on introducing the field of endocytobiology."; "It had been known that sponges somehow took in dissolved organic matter, but it remained unclear whether they could do it on their own or needed help from their bacterial symbionts."Synonyms: symbiote