Definition of mountain fever in US English:

mountain fever

noun

  • 1A malarial or typhoid fever contracted in a mountain region.

  • 2US. Disorientation or confusion experienced in mountainous country, due either to inexperience or to altitude sickness.

Origin

Mid 19th century. From mountain + fever.

Pronunciation

mountain fever

/ˌmaʊntɪn ˈfiːvə/