Origin: 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.
alternative forms: matress.
2. (Science: physics) a mass of interwoven brush, poles, etc, to protect a bank from being worn away by currents or waves.