The word Rococo was apparently a combination of rocaille and barocco (Baroque). It was used formally as an art-historical term from the middle of the 19th century. It is now generally accepted, though its exact definition has been much debated. Purists might argue that Rococo, with its love of shell-like curves and S- and C-curves, was essentially a style of decoration and should be applied to art forms such as boiserie, metalwork, furniture, and porcelain. Today its wider use is generally countenanced, however, and it is also applied to painting, sculpture, and architecture. Watteau is widely considered to have been the first great Rococo painter and Boucher and Fragonard the masters of its mature style. In sculpture Falconet has often been thought the pre-eminent Rococo practitioner and many of his designs were reproduced in porcelain. In architecture its influence spread rapidly abroad, particularly to southern Germany and Austria where it is evident in churches such as Vierzehnheiligen and Die Wies. However, certain architectural historians would argue that this Germanic Rococo was in fact a manifestation of late Baroque rather than a new stylistic development.