- thynnin
- thyroglobulin
- thyroid binding globulin, TBG
- thyroliberin
- thyronine
- thyrotropin, TSH
- toxicosozin
- toxin
- toxoid
- trailing ion
- transcortin
- transcriptase
- transcription
- transcription factor
- transdeamination
- transduction
- transfection
- transfer factor, TF
- transfer RNA, tRNA
- transferase
- transferrin, iron binding globulin
- transformation
- transforming factor
- transition state
- translation
- transmembrane protein
- transport piece
- transposition
- transposon
- trehalose
- triacylglycerol
- tricarboxylic acid cycle, Krebs cycle
- trichosanthin
- triplet
- trisaccharide
- tropocollagen
- tropoelastin
- tropomyosin
- troponin
- trypsin
- trypsin inhibitor
- tryptophane, Trp
- tuberculostearic acid
- tubulin
- tumor necrosis factor, TNF
- turanose
- two-dimensional electrophoresis
- tyramine
- tyrosine, Tyr
- tyvelose