Geometry, a plain figure with ten sides and ten angles.

Decacynia (from δέκα, ten, and γυνή, a woman), the name of an order, or secondary division, in the class decandra, of the sexual method, consisting of plants whose flowers are furnished with ten stamens and the same number of styles; which last are considered by Linnaeus and the sexualists as the female organs of generation in plants. Neurada and American nightshade furnish examples.