Angiosperm: a subdivision of the seed plants generally known as the flowering plants; characterized by plants that produce seeds within one or more closed carpels

Anther: the pollen-containing part of the stamen

Bilateral/Irregular: the perianth parts are dissimilar so that they can only be divided into equal parts along one vertical plane.

Calyx: the outermost whorl of floral appendages; the collective term for the sepals of a flower

Carpel: the ovule-bearing structure of a flower, usually consisting of a stigma, style, and ovary

Complete Flowers: flowers having all four characteristic parts: sepals, petals, stamens, and carpels

Corolla: the second whorl of floral appendages; the collective term for the petals of a flower

Dichotomous: forked or splitting into pairs; refers to a type of identification key based on successive choices between two statements

Family: a classification category between order and genus

Filament: the stalk of a stamen which supports the anther

Fruit: the mature or ripened ovary of a flower; usually containing seeds

Imperfect flowers: flowers that have only one kind of sex organ (stamens or carpels); also known as unisexual flowers

Incomplete flowers: flowers that are missing one or more floral parts (sepals, petals, stamens, or carpels)

Irregular flowers: flowers in which the perianth parts of each kind are dissimilar so that a flower may be divided into equal halves only along one vertical plane; said to have bilateral symmetry

Ovary: the ovule-bearing region of a carpel which usually develops into a fruit

Ovule: a minute structure within the ovary which will, if successfully fertilized, develop into a seed

Pedicel: the stalk of a single flower

Perfect flowers: flowers that have both stamens and carpels

Perianth: the collective term for the calyx and corolla of a flower

Petals: a single member of the corolla; often brightly colored and showy

Pistil: a female structure within the flower, consisting of a stigma, style, ovary; a pistil may consist of one carpel or of many (see carpel)

Pollen: the microscopic spores borne within the anther of a stamen and which produce male gametes

Pollination: the process of transferring pollen from site of production (see anther) to the site of reception (see stigma)

Radial/Regular: perianth parts are similar in size and shape so that a flower can be divided into three or more equal pie-shaped slices

Receptacle: the floral axis from which the various flower parts arise

Regular flowers: flowers in which the perianth parts of each kind are similar so that a flower may be divided into equal portions along a vertical plane in various directions; said to have radial symmetry

Seed: a mature ovule containing an embryo surrounded by a seed coat

Sepal: a single member of the calyx; often green and resembling a small leaf

Stamen: the male reproductive structure of a flower, composed of an anther and a filament

Stigma: the terminal portion of a carpel, where pollen is received and germinates

Style: the region of the carpel between the stigma and the ovary

Whorl: a circle of three or more similar parts arising from a common node