Clematis derives from Latin clematis, borrowed from Greek klēmatis ("climbing plant, vine branch"), from klēma ("vine branch, twig"), from the verb klan ("to break off"). The etymological image is of a plant whose stems are brittle and easily snapped — an accurate observation of many clematis species, whose apparently robust vines are surprisingly fragile at the joints.
The genus Clematis belongs to the family Ranunculaceae (buttercup family) and encompasses over 300 species distributed across every continent except Antarctica. Species range from vigorous woody climbers that can cover walls and arbors to delicate herbaceous perennials. The flowers — which in many species are technically composed of colored sepals rather than true petals — come in virtually every color: white, pink, red, purple, blue, yellow, and bicolors.
In English folk tradition, the native species Clematis vitalba has accumulated charming vernacular names. "Traveller's joy" describes its habit of draping itself over hedgerows along roadsides and footpaths, creating corridors of white blossom in summer. "Old man's beard" refers to the fluffy, silvery seed heads that persist through winter, giving hedgerows a grey, bearded appearance. "Virgin's bower" — a name also applied
The clematis has been cultivated in European and Asian gardens for centuries. Chinese species like C. florida and C. patens, introduced to Europe in the 18th and 19th centuries, provided the genetic material for the large-flowered hybrid clematis that dominate modern gardens. Japanese gardeners had been cultivating clematis (kazaguruma, "windmill," for the flower shape) since at least the Edo period.
The genus name has generated persistent debate about pronunciation. British gardeners traditionally say /klɪˈmeɪ.tɪs/ (with stress on the second syllable), while American usage varies between /ˈklɛm.ə.tɪs/ (first syllable stress) and the British form. The Greek original stressed the first syllable, which supports the American pronunciation, but usage has never been standardized.