Source : Webster's Revised Unabridged Dictionary (1913)

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 ?etals. The narcissus and daffodil are members of
   this family.