מ Mem, the thirteenth letter of the Alphabet. It interchanges with נ, esp. in the plural termination ִים, (Chald.) ִין, e. g. קוֹרְאִין = קוֹרְאִים, חִטִּין = חִטִּים &c., with ב, v. letter ב.—מ is frequently inserted for emphasizing a succeeding labial, cmp. סַמְפִּירִינוֹן a. סַפִּיר, זַמְבְּלִיגָא a. זַבְלִיגָא &c.—מ as a preformative letter in denominatives, e. g. מִזְבֵּחַ from זבח, מַדְבְּחָא from דבח, מְאוֹרָע from ארע &c.