isopleth has definitions from the field of geography
1
[ noun ] (geography) a line drawn on a map connecting points having the same numerical value of some variable

Synonyms

isarithm isogram

Used in print

(LeRoy Fothergill, "Biological Warfare", in Peter...)

From these dosage isopleths it can be seen that an area of over 34000 square_miles was covered .

As can be seen from these dosage isopleths , approximately 100 square_miles was covered within the area sampled .

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