Isobar and Isarithm

Isobar noun - (meteorology)an isogram connecting points having equal barometric pressure at a given time.

Isarithm and isobar are semantically related. In some cases you can use "Isarithm" instead a noun "Isobar".

Isarithm noun - A line drawn on a map connecting points having the same numerical value of some variable.

Isobar and isarithm are semantically related. Sometimes you can replace term "Isobar" with "Isarithm", this nouns are similar.