Modernize is a word that starts with m and means to upgrade.
Make is a word that means to create and starts with "m".
manducate
my
A four letter word that starts with J and ends with M: jism.
-Mad-Me
methionylglutaminylarginyltyrosylglutamylseryllleucylpheny
A muscle is a 7 letter word that starts with m and helps you run fast.
A seven (7) letter word that starts with M and ends with O: memento
One very long word that starts with m is: microcryptocrystalline (22 letters)
marjoram
minimum