D defs.my
Entry 2 senses Webster, 1913

Turtleback

/(tûr"t'l-băk`)/ · Tur·tle·back · IPA
01 n. A rude stone celt of a form suggesting the back of a turtle.
  1. 1.
    A rude stone celt of a form suggesting the back of a turtle.(Archaeol.)
  2. 2.
    A convex deck at the bow or stern of a vessel, so made to shed the seas quickly.(Naut.)