Skip to Content


Pronunciation: pers'pi-ra'shun


  1. The excretion of fluid by the sweat glands of the skin.
  2. All fluid loss through normal skin, whether by sweat gland secretion or by diffusion through other skin structures.
  3. The hypotonic fluid excreted by the sweat glands; it consists of water containing sodium chloride and phosphate, urea, ammonia, ethereal sulfates, creatinine, fats, and other waste products; the average daily quantity is estimated at about 1500 g.

Synonym(s): diaphoresis, sudation, sweating

[L. per-spiro, pp. -atus, to breathe everywhere]

See Also: sweat

Disclaimer: This site is designed to offer information for general educational purposes only. The health information furnished on this site and the interactive responses are not intended to be professional advice and are not intended to replace personal consultation with a qualified physician, pharmacist, or other healthcare professional. You must always seek the advice of a professional for questions related to a disease, disease symptoms, and appropriate therapeutic treatments.
© Copyright 2018 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.