Mohair.  A man in the civil line, a townsman, or tradesman: 
  a military term, from the mohair buttons worn by persons
  of those descriptions, or any others not in the army, the
  buttons of military men being always of metal:  this is
  generally used as a term of contempt, meaning a bourgeois,
  tradesman, or mechanic.

Moiety.  Half, but vulgarly used to signify a share or portion: 
  as, He will come in for a small moiety.

Moll.  A whore.

Moll PEATLY’S gig.  A rogering bout.

Moll Thompson’s mark.  M. T. i.e. empty:  as, Take
  away this bottle, it has Moll Thompson’s mark upon it.

Molly.  A Miss Molly; an effeminate fellow, a sodomite.

Monday.  Saint Monday.  See saint.

Money.  A girl’s private parts, commonly applied to little
  children:  as, Take care, Miss, or you will shew your
  money.

Money droppers.  Cheats who drop money, which they
  pretend to find just before some country lad; and by way
  of giving him a share of their good luck, entice him into a
  public house, where they and their confederates cheat or
  rob him of what money he has about him.

Mongrel.  A hanger on among cheats, a spunger; also a
  child whose father and mother are of different countries.

Monks and friars.  Terms used by printers:  monks are
  sheets where the letters are blotted, or printed too black;
  friars, those letters where the ink has failed touching the
  type, which are therefore white or faint.

Monkey.  To suck the monkey; to suck or draw wine, or
  any other liquor, privately out of a cask, by means of a
  straw, or small tube.  Monkey’s allowance; more kicks
  than halfpence.  Who put that monkey on horseback without
  tying his legs? vulgar wit on a bad horseman.

Monosyllable.  A woman’s commodity.

MOONCURSER.  A link-boy:  link-boys are said to curse the
  moon, because it renders their assistance unnecessary;
  these gentry frequently, under colour of lighting passengers
  over kennels, or through dark passages, assist in robbing
  them.  Cant.

Moon-eyed hen.  A squinting wench.

Moon men.  Gypsies.

Moon Rakers.  Wiltshire men:  because it is said that
  some men of that county, seeing the reflection of the
  moon in a pond, endeavoured to pull it out with a rake.

Moonshine.  A matter or mouthful of moonshine; a trifle,
  nothing.  The white brandy smuggled on the coasts of
  Kent and Sussex, and the gin in the north of Yorkshire,
  are also called moonshine.

Mop.  A kind of annual fair in the west of England, where
  farmers usually hire their servants.