isocryme vs isopleth

isocryme and isopleth both are nouns.

Word	Noun	Adjective	Verb	Adverb
isocryme	Yes	No	No	No
isopleth	Yes	No	No	No

As nouns, isopleth is a hypernym of isocryme; that is, isopleth is a word with a broader meaning than isocryme:

isocryme: a line connecting points on the earth's surface having the same mean temperature in the coldest month of the year.
isopleth: a line drawn on a map connecting points having the same numerical value of some variable

Other hypernyms of isocryme include isarithm, isogram.

isocryme (noun)	isopleth (noun)
a line connecting points on the earth's surface having the same mean temperature in the coldest month of the year.	a line drawn on a map connecting points having the same numerical value of some variable