An ecoparasite that becomes pathogenic in consequence of weakened resistance on the part of its host. ... (05 Mar 2000) ... 
(zen″o-par´ә-sīt) an organism not usually parasitic on a particular species, but which becomes so because of a weakened condition of the host.
Type: Term Pronunciation: zen′ō-par′ă-sīt Definitions: 1. An ecoparasite that becomes pathogenic as a consequence of its host's weakened resistance.
xenoparasite, xenoparasitism 1. An ectoparasite that becomes pathogenic when the resistance of its host weakens. 2. A strange organism not usually parasitic on the host but that becomes so because of a weakened condition of the host.