Operational definition

Umbrella ecological role.

A heterotrophic organism that obtains organic matter, chemical free energy, or nutrients from biomass or biologically produced organic material originating in other organisms.

Consumers include, in the broad sense:

The subordinate terms identify how and from what state of biomass consumption occurs.

100.1 Primary consumer

Consumes primary producers.

100.2 Secondary or higher consumer

Consumes other consumers.

100.3 Omnivore

Acquires resources across multiple trophic positions.

100.4 Microbial consumer

Consumes cells, dissolved metabolites, or particulate organic matter.