1. Living or active in the absence of free oxygen
   - anaerobic

See also: anaerobe

• genus Triops
• genus Triostium
• genus Tripleurospermum
• genus Triplochiton
• genus Triticum
• genus Triturus
• genus Trogium
• genus Troglodytes
• genus Trogon
• genus Trollius
• genus Trombicula
• genus Tropaeolum
• genus Tropidoclonion
• genus Truncocolumella
• genus Tsuga
• genus Tuber
• genus Tubercularia
• genus Tulestoma
• genus Tulipa
• genus Tulostoma
• genus Tunga
• genus Tupaia
• genus Tupinambis
• genus Turbatrix
• genus Turdus