Meaning of saturated vapor

sat'urated va'por

Pronunciation: [key]
— Thermodynam. Thermodynam.
  1. a vapor whose temperature and pressure are such that any compression of its volume at constant temperature causes it to condense to liquid at a rate sufficient to maintain a constant pressure. Cf.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.