isarithm

/ˈaɪsəˌrɪðəm/
noun
  1. A line on a map or chart connecting points of equal value for a given variable, such as temperature, rainfall, or elevation.
    • The weather map used isarithms to show areas with the same amount of rainfall.
    • The isarithm for temperature clearly showed a warm band across the southern states.
    • Topographic maps use isarithms called contour lines to represent elevation.
Synonyms
What does "isarithm" mean? | whatsthatwordmean | whatsthatwordmean