sudation vs transpiration

sudation

noun
  • Perspiration; sweat (fluid). 

  • The process of perspiring. 

transpiration

noun
  • The process of giving off water vapour through the skin or mucous membranes. 

  • The loss of water by evaporation in terrestrial plants, especially through the stomata; accompanied by a corresponding uptake from the roots. 

  • The passage of gases through fine tubes. 

How often have the words sudation and transpiration occurred in a corpus of books? (source: Google Ngram Viewer )