Friedrich Kluge2512113An Etymological Dictionary of the German Language, M — Mai1891John Francis Davis
Mai, m., from the equiv. MidHG. meie, OHG. meio, m., ‘May.’ Borrowed from Lat. Mâjus (comp. Ital. maggio, Fr. mai), ‘May,’ at the same period as August, März, and Jänner (old form for Januar).