Caryophyllaceæ, a natural order of thalamifloral dicotyledons, containing from 800 to 1000 known species, mostly herbaceous plants, a few half shrubby, easily recognised by their opposite entire exstipulate leaves, stem swollen at the joints, and placentation free central, at least at maturity.
In the restricted sense, the order is divided into Sileneæ, with calyx united, and Alsineæ, with sepals separate. Many of the former produce beautiful flowers—e.g. pink, carnation, sweet-william, lychnis, &c., but the latter and lower group are largely inconspicuous weeds—chickweed, spurrey—and furnish gradations to Portulacaceæ, Paronychiaceæ, Amaranthaceæ, and Chenopodiaceæ. The plants of this order are mostly natives of temperate and cold countries in the old world. Almost all are insipid and inert; a few contain saponine, and afford a substitute for soap. See SOAPWORT.