Definition of rarefier in English:

rarefier

(also rarifier)

noun

rare
  • Something that rarefies, especially an apparatus for pumping air out of a vessel.

Origin

Late 16th century; earliest use found in Thomas Nashe (d. c1601), writer. From rarefy + -er.

Pronunciation

rarefier

/ˈrɛːrɪfʌɪə/