天然放射性同位体

てんねんほうしゃせいどういたい

noun

•

natural radioisotope

天	heavens, sky, imperial
然	sort of thing, so, if so, in that case, well
放	set free, release, fire, shoot, emit, banish, liberate
射	shoot, shine into, onto, archery
性	sex, gender, nature
同	same, agree, equal
位	rank, grade, throne, crown, about, some
体	body, substance, object, reality, counter for images