Chair back with top rail curved up at center. Also a curved-back sofa with hump in the center.

Back of late Chippendale or Hepplewhite style, the top rail of which was in the form of a serpentine curve.

Triple-curved chairback frame with a raised central curve. A pierced-shield design, such as honeysuckle or anthemion, spans the back from the seat to the high curve.

a backpack that has a hydration system built into it

See Types of Elements.