Word Study
arbalest
CIDE DICTIONARY
arbalest, n. [OF. arbaleste, LL. arbalista, for L. arcuballista; arcus bow + ballista a military engine. See Ballista.].
A crossbow, consisting of a steel bow set in a shaft of wood, furnished with a string and a trigger, and a mechanical device for bending the bow. It served to throw arrows, darts, bullets, etc. Fosbroke. [1913 Webster]
OXFORD DICTIONARY
arbalest, n. (also arblast) hist. a crossbow with a mechanism for drawing the string.
Etymology
OE arblast f. OF arbaleste f. LL arcubalista f. arcus bow + BALLISTA
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