a family of dicotyledonous plants. They are grasses, more rarely bushes and trees. The leaves are usually opposite, less often verticulate, at times sequential; they are integral and either lack stipules or have very small ones. The blossoms are bisexual and solitary or gathered in a ring, brush, or dichasium. The gynecium is composed of two to six seed leaves, with the germ at the top; the fruit is usually a pod.

There are approximately 25 genera and more than 500 species, primarily in tropical and subtropical regions, particularly in the tropics of America. In the USSR there are five genera including some 25 species, of which 14 are of the genus Lythrum. Lythraceae from the genera Rothala and Ammania are weeds in rice fields. Lythraceae give valuable wood in some tropical varieties, such as the Brazilian rose-wood (Physocalymma scaberrimum). There are also some varieties that produce dyes, including Lawsonia, which gives henna. Certain Lythraceae are cultivated as decorative plants.