NOUN (2)

1. the branch of the biological sciences dealing with the functioning of organisms;

2. processes and functions of an organism;

The Collaborative International Dictionary of English v.0.48:

physiology \phys`i*ol"o*gy\ (f[i^]z`[i^]*[o^]l"[-o]*j[y^]), n.;
   pl. Physiologies. [L. physiologia, Gr. fysiologi`a; fy`sis
   nature + lo`gos discourse: cf. F. physiologie.]
   1. The science which treats of the phenomena of living
      organisms; the study of the processes incidental to, and
      characteristic of, life.
      [1913 Webster]

   Note: It is divided into animal and vegetable physiology,
         dealing with animal and vegetable life respectively.
         When applied especially to a study of the functions of
         the organs and tissues in man, it is called human
         physiology.
         [1913 Webster]

   2. A treatise on physiology.
      [1913 Webster]

   Mental physiology, the science of the functions and
      phenomena of the mind, as distinguished from a
      philosophical explanation of the same.
      [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

38 Moby Thesaurus words for "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