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1. (printing) a unit of measurement used in typesetting, equal to the point size of the current font
   "since 'em quad' is hard to distinguish from 'en quad', printers sometimes called it a 'mutton quad'";
   - em quad, mutton quad
    
2. A linear unit (1/6 inch) used in printing
   - pica em, pica
    
3. The 13th letter of the Roman alphabet
   - M, m

1. Make, turn into, put into (em- is used before a p or b)
   - en-

Derived forms: ems

Type of: alphabetic character, area unit, letter, letter of the alphabet, linear measure, linear unit, square measure

Part of: in, inch, Latin alphabet, Roman alphabet

Encyclopedia: Em, David