rare earths
rare; scarce; sparse; watery
dust; earth; ground; homemade; land; local; soil; unrefined
【医】 clay; earth; geo-; terra; terrae
a group of things with common features; clan; family; race; strain
【化】 alkaline earths; family; group; odd series; periodic family; sub-group
subgroup
【医】 group; race; series; tribe