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swan's neck pediment

or swan neck pediment

noun Architecture, Furniture.
  1. a broken pediment, the outline of which consists of a pair of S-curves tangent to the cornice level at the ends of the pediment, rising to a pair of scrolls on either side of the center, where a finial often rises between the scrolls.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018