Word Study
isogeotherm
CIDE DICTIONARY
isogeotherm, n. [Iso- + Gr. gh^ the earth + qe`rmh heat.].
A line or curved surface passing beneath the earth's surface through points having the same mean temperature.
OXFORD DICTIONARY
isogeotherm, n. a line or surface connecting points in the interior of the earth having the same temperature.
Derivative
isogeothermal adj.
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