Proverbs 25:18

a maul "i.e. a hammer, a variation of mall, from malleus… The Hebrew and English alike occur in Proverbs 25:18 only. But a derivative from the same root, and differing only slightly in form, is found in Jeremiah 51:20, and is there translated by -battle-axe" (or maul, R.V. marg.) how incorrectly is shown by the constant repetition of the verb derived from the same root in the next three verses, and there uniformly rendered -break in pieces" … There is no doubt that some heavy warlike instrument, a mace or club, is alluded to; probably such as that which is said to have suggested the name of Charles Martel.… A similar word is found once again in the original of Ezekiel 9:2 =-weapon of smashing" (A.V. and R.V. text, -slaughter-weapon)." The sequel shows how terrible was the destruction such weapons could effect." Smith's Dict. of Bible, Art. Maul. See note in this Series on Jeremiah 51:20.

It is difficult to see why in this and the following verse (though not in Proverbs 25:14, or Proverbs 25:26,) R.V. should have followed A.V. in inverting the order of the two clauses in the Hebrew.