Definition of microtherm in US English:

microtherm

noun

Ecology
  • A plant (or other organism) that can grow or survive in a cold environment.

adjective

Ecology
  • Designating a microtherm.

Origin

Late 19th century; earliest use found in Nature: a weekly journal of science. From micro- + -therm, after French microtherme.

Pronunciation

microtherm

/ˈmʌɪkrə(ʊ)θəːm/