- A branch of biology that deals with the functions and activities of life or of living matter (as organs, tissues, or cells) and of the physical and chemical phenomena involved.
- (obsolete) The study and description of natural objects; natural science.
- animal physiology
- plant physiology
aerobiology, agrobiology, anatomy, astrobiology, bacteriology, biochemics, biochemistry, biochemy, bioecology, biological science, biology, biometrics, biometry, bionics, bionomics, biophysics, botany, cell physiology, cryobiology, cybernetics, cytology, ecology, electrobiology, embryology, enzymology, ethnobiology, exobiology, genetics, gnotobiotics, life science, microbiology, molecular biology, pharmacology, radiobiology, taxonomy, virology, xenobiology, zoology