נֶ֫תֶר noun [masculine] natron, or carbonate of soda, a mineral alkali (Late Hebrew = Biblical Hebrew; Aramaic נִתְרָא, ; compare Greek νίτρον, λίτρον, Latin nitrum (see Lexicons)); — אִםתְּֿכַבְּסִי בַּנֶּתֶר Jeremiah 2:22 though thou wash thyself with natron (figurative; "" בֹּרִית; on use of 'nitrum' for handwashing among Greeks see Meineke^{Fragm. Comicorum ii. 638}); חֹמֶץ עַלנָֿ֑תֶר Proverbs 25:20 (figurative of the incompatible).