Source : Webster's Revised Unabridged Dictionary (1913)

Dead-eye \Dead"-eye`\, n. (Naut.)
   A round, flattish, wooden block, encircled by a rope, or an
   iron band, and pierced with three holes to receive the
   lanyard; -- used to extend the shrouds and stays, and for
   other purposes. Called also {deadman's eye}. --Totten.