ROLLING-SWELL. That heaving of the sea where the waves are very distant, forming deep troughs between.

ROLLING-TACKLES. Used to prevent the yards from swaying to and fro under heavy rolling motion.

ROLLSTER, or Roster. A rotation list of officers.

ROLL UP A SAIL, To. To hand it quickly.

ROMAN CEMENT. A cement which hardens under water; used for piers, docks, &c., as pozzolana, Aberthaw limestone, &c.

ROMBOWLINE, or Rumbowline. Condemned canvas, rope, and the like. Also the coarse rope used to secure new coils.

RONDEL. An old term for a light, round shield.

RONE. A northern term for the roe of a fish.

RONNAL. A northern term for a female fish, as kipper is for the male.

ROOBLE. A Russian coin. (See [Ruble].)