art nouveau

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A style of decoration and architecture of the late 19th and early 20th centuries, characterized particularly by the depiction of leaves and flowers in flowing, sinuous lines.

from The Century Dictionary.

• A name given to a secession movement in art which had its origin in Paris at the close of the nineteenth century, and is still in process of development.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A decorative style of art and architecture that especially used the sinuous and flowing lines of plants.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a French school of art and architecture popular in the 1890s; characterized by stylized natural forms and sinuous outlines of such objects as leaves and vines and flowers