Word Study
liliidae
CIDE DICTIONARY
liliidae, prop. n.
one of four subclasses or superorders of Monocotyledones; it comprises 17 families including: Liliaceae ; Alliaceae ; Amaryllidaceae ; Iridaceae ; Orchidaceae ; Trilliaceae . [WordNet 1.5]
For further exploring for "liliidae" in Webster Dictionary Online