n. (Gr. monos, single; kotyledon, cup-shaped hollow) a class of angiosperms having an embryo with only one cotyledon, part of the flower usually in threes, leaves with parallel veins, and scattered vascular bundles.

One of the two main groups of flowering plants ( see Angiosperms). Characterized normally by the presence of just a single seedling leaf (cotyledon) and commonly by floral parts arranged in threes, parallel leaf veins and the inability to form secondary tissues, e.g. wood, from cell division within the tissues.

Flowering plants are separated into two classes: Magnoliopsida (dicotyledons) and Liliopsida (monocotyledons). The class Liliopsida is composed entirely of "monocots" and these plants are distinguished by: one cotyledon (seed leaves that provide nourishment to the developing seedling), parallel veins and 3-merous (or multiples of 3) flowers.