HELIUM
none. Light inert gaseous element used in airships and as a refrigerant. [related to *helio-]
none. Light inert gaseous element used in airships and as a refrigerant. [related to *helio-]
none. Light inert gaseous element used in airships and as a refrigerant. [related to *helio-]
none. Light inert gaseous element used in airships and as a refrigerant. [related to *helio-]