1. any of various ornamental climbing plants of the genus Clematis usually having showy flowers;
The Collaborative International Dictionary of English v.0.48:
Clematis \Clem"a*tis\ (kl[e^]m"[.a]*t[i^]s), n. [NL., fr. Gr.
klhmati`s brushwood, also (from its long, lithe branches)
clematis. fr. klh^ma twig, shoot, fr. kla^n to break off.]
A genus of flowering plants, of many species, mostly
climbers, having feathery styles, which greatly enlarge in
the fruit; -- called also virgin's bower.
WordNet (r) 3.0 (2006):
n 1: any of various ornamental climbing plants of the genus
Clematis usually having showy flowers