Liliopsida

Definition
noun
(plant taxonomy) A taxonomic class of the division Magnoliophyta comprised of lilies, grasses, palms, orchids, and other monocots
Supplement
The flowering plants (angiosperms) that make up the division Magnoliophyta may be grouped into two major plant groups: Dicotyledoneae (or Magnoliopsida) and Monocotyledonae. The Dicotyledonae includes all the dicots whereas the Monocotyledonae, or Liliopsida, includes all the monocots. According to the Cronquist system of classification of flowering plants, the monocotyledons make up the taxonomic class of Liliopsida and is comprised of 19 orders and 65 families.¹
The Liliopsida consists of angiosperms that are characterized by having only one cotyledon in the seed and an endogenous manner of growth. Apart from the number of cotyledons, other identifying characteristics are as follows:

• the number of parts of flower – monocot flowers are trimerous (in multiples of three)
• the number of pores in pollen – monocots have one
• arrangement of vascular bundles in the stem – in monocots, the vascular bundles are scattered
• the roots – monocot roots are adventitious roots
• the arrangement of major leaf veins – in monocots, the leaves have parallel venation.

Scientific classification:

Kingdom: Plantae

Division: Magnoliophyta

Class: Liliopsida

See also:

• monocot
• angiosperm

Reference(s):

¹ Cronquist, A (1981). An integrated system of classification of flowering plants. New York: Columbia University Press.