等とう温おん線せん

noun

isotherm

A line on a map or chart connecting points of equal temperature. Used in meteorology, oceanography, and thermodynamics.

• 天てん気き図ずの等とう温おん線せんを見みると、前ぜん線せんの位い置ちがわかる。

  By looking at the isotherms on the weather map, you can see the position of the front.