Definitions:

1. A biologist who specializes in the classification of organisms into groups on the basis of their structure, origin and behavior. NOUN
   • The taxonomer identified the new species and placed it within its proper classification in the animal kingdom.
2. An individual who classifies organisms or things in an orderly system that indicates natural relationships, based on a variety of characteristics. NOUN
   • The taxonomer meticulously classified organism based on shared characteristics.

Synonyms:

• organism classifier
• species identifier
• systematist