isotherm

[ ahy-suh-thurm ]

noun

1. Meteorology. a line on a weather map or chart connecting points having equal temperature.
2. Also called isothermal line. Physics. a curve on which every point represents the same temperature.

isotherm

/ ˈaɪsəʊˌθɜːm /

noun

1. a line on a map linking places of equal temperature
2. physics a curve on a graph that connects points of equal temperature

isotherm

/ ī′sə-thûrm′ /

1. A line drawn on a weather map connecting points that have the same temperature. Each point can mark one temperature reading or an average of several readings.

Word History and Origins

Origin of isotherm¹

First recorded in 1855–60; back formation from isothermal

Example Sentences

He invented isotherms, the wavy lines — now familiar from weather maps — that link areas around the globe that have the same temperature.

From Nature

Out there is the endless possibility of night stretching out in every direction; in here, the thoughts and emotions ebb and flow in response to the body’s changing isotherms.

From The Guardian

So as things warm up the temperature isotherm doesn’t shift nearly as far as it does in a flat place.

From Washington Times

Humboldt also created isotherms, those lines you see on weather maps that connect points with the same temperature.

From New York Times

He introduced the idea of vegetation zones slung around the globe; he also invented isotherms, lines of equal temperature.

From Economist