Word Study
Isocheim
CIDE DICTIONARY
Isocheim, n. [Iso- + Gr. , , winter.].
A line connecting places on the earth having the same mean winter temperature. Cf. Isothere.
OXFORD DICTIONARY
Isocheim, n. a line on a map connecting places having the same average temperature in winter.
Etymology
ISO- + Gk kheima winter weather
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