Mat"tress (?), n. [OF. materas,
F. matelas, LL. matratium; cf. Sp. & Pg.
almadraque, Pr. almatrac; all from Ar.
ma&tsdot;rah a place where anything is thrown, what is thrown
under something, fr. &tsdot;araha to throw.]
1. A quilted bed; a bed stuffed with hair,
moss, or other suitable material, and quilted or otherwise
fastened. [Written also matress.]
2. (Hydraulic Engin.) A mass of
interwoven brush, poles, etc., to protect a bank from being worn away
by currents or waves.