Sackbut

n. [ F. saquebute, OF. saqueboute a sackbut, earlier, a sort of hook attached to the end of a lance used by foot soldiers to unhorse cavalrymen; prop. meaning, pull and push; fr. saquier, sachier, to pull, draw (perhaps originally, to put into a bag or take out from a bag; see Sack a bag) + bouter to push (see Butt to thrust). The name was given to the musical instrument from its being lengthened and shortened. ] (Mus.) A brass wind instrument, like a bass trumpet, so contrived that it can be lengthened or shortened according to the tone required; -- said to be the same as the trombone. [ Written also sagbut. ] Moore (Encyc. of Music). [ 1913 Webster ]

☞ The sackbut of the Scriptures is supposed to have been a stringed instrument. [ 1913 Webster ]