Source : Webster's Revised Unabridged Dictionary (1913)

Dunnage \Dun"nage\, n. [Cf. {Dun} a mound.] (Naut.)
   Fagots, boughs, or loose materials of any kind, laid on the
   bottom of the hold for the cargo to rest upon to prevent
   injury by water, or stowed among casks and other cargo to
   prevent their motion.