Real Dictionary

partial pressure in American English
noun: the pressure that a gas in a mixture of gases would exert if it occupied the same volume as the mixture at the same temperature

partial pressure in British English
noun: the pressure that a gas, in a mixture of gases, would exert if it alone occupied the whole volume occupied by the mixture

partial pressure in the Oil and Gas Industry
noun: Partial pressure is the pressure that an individual gas exerts in a mixture of gases, which in distillation can have an effect on boiling, so pressure may have to be increased to achieve the boiling temperature.