Kalmar "nephrolith" tana nufin yanayin kiwon lafiya da ke nuna kasancewar dutse (wanda aka fi sani da calculus) a cikin koda. An samo kalmar daga kalmomin Helenanci "nephros," ma'anar koda, da "lithos," ma'ana dutse. Nephroliths kuma ana kiransu da duwatsun koda.
