Origin: ModL: so named (1818) by Baron Jöns Jakob Berzelius < Gr selēnē, the moon (see Selene) + -ium, by analogy with tellurium, with which it was assoc. in the ore
See selenium in American Heritage Dictionary 4
noun Symbol Se
Origin: Greek selēnē, moon (from selas, light, brightness)
Origin: + -ium.
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