isarithm vs isogram

isarithm and isogram both are nouns.

Word	Noun	Adjective	Verb	Adverb
isarithm	Yes	No	No	No
isogram	Yes	No	No	No

As nouns, isarithm and isogram are synonyms defined as:

isarithm and isogram: a line drawn on a map connecting points having the same numerical value of some variable

Other synonyms of isarithm include isopleth.

isarithm (noun)	isogram (noun)
a line drawn on a map connecting points having the same numerical value of some variable	a line drawn on a map connecting points having the same numerical value of some variable