bioindicator Syllabification: (bi·o·in·di·ca·tor)Pronunciation: /ˌbīōˈindiˌkātər/Definition of bioindicator noun an organism whose status in an ecosystem is analyzed as an indication of the ecosystem’s heath. Derivatives bioindicationPronunciation: /-ˌindiˈkāSHən/ noun bioindicator in other Oxford dictionaries Definition of bioindicator in the British & World English dictionary