Amaryllidaceous \Am`a*ryl`li*da"ceous\, Amaryllideous \Am`a*ryl*lid"e*ous\, a. (Bot.) Of, pertaining to, or resembling, an order of plants differing from the lily family chiefly in having the ovary below the petals. The narcissus and daffodil are members of this family. [1913 Webster]