MORION is a 6 letter word that starts with M.

1. \Mo"ri*on\, n. [F. morion, Sp. morrion; cf. Sp. morra the
   upper part of the head, morro anything that is round.]
   A kind of open helmet, without visor or beaver, and somewhat
   resembling a hat.
   
         A battered morion on his brow.           --Sir W.
                                                  Scott.
   
   

2. \Mo"ri*on\, n. [G.] (Min.)
   A dark variety of smoky quartz.