moulding

Any continuous projecting or inset architectural member with a contoured profile. It defines, casts shadows, enriches, emphasizes, and separates, and is usually horizontal or vertical, although it occurs around arches and vaults. It is an essential part of architraves, bases, entablatures, and string-courses, and is found in virtually all periods of architecture except the International Modern Movement from which it was expunged. It occurs in many forms in the Classical Orders (e.g. astragal, bead, cavetto, cyma, fillet, flute, ovolo, scotia, and torus), Romanesque work (e.g. beak-head, billet, chevron, hollows, rounds, and splays), and Gothic (e.g. deep rounds, and hollows, ball-flower, dog-tooth, keels, nail-head, etc.). See bead; beak-head; bolection; bowtell; cable; cant; cavetto; chaplet; chevron; dancette; dog-tooth; dovetail; echinus; edge-roll; fascia; gadroon; gorge; hood; label; nail-head; nebule; ogee; ovolo; pellet; ressault; roll; running dog; wave. See also Orders.

The noun has 4 meanings:

Meaning #1: a decorative strip used for ornamentation or finishing
  Synonym: molding

Meaning #2: a decorative recessed or relieved surface on an edge
  Synonyms: molding, border

Meaning #3: sculpture produced by molding
  Synonyms: mold, mould, molding, modeling, clay sculpture

Meaning #4: a preliminary sculpture in wax or clay from which a finished work can be copied
  Synonyms: modeling, modelling, molding