E. Cobham Brewer 1810–1897. Dictionary of Phrase and Fable. 1898.
Dead-eye,
in nautical phrase, is a block of wood with three holes through it, for the lanyards of rigging to reeve through, without sheaves, and with a groove round it for an iron strap. (Dana: Seaman’s Manual, p. 92.)
The holes are eyes, but they are dead eyes.
