Isotherm

Real World Example

Imagine trying to find people at a party who are all wearing the same colored shirt. This is similar to an isotherm on a weather map, which connects points that have the exact same temperature. Just like you would scan through the party to spot everyone with, say, a blue shirt and group them together, an isotherm traces a path through different locations on the map that all share the same temperature at a given time, effectively 'grouping' those areas together by temperature.