M

1. mach.

2. Music. major.

3. male.

4. married.

5. Medieval.

6. medium.

7. mega-.

8. Middle.

9. modal auxiliary.

10. modifier.

11. Econ. monetary aggregate: issued periodically by the Federal Reserve Board as various measures of money supply (M-1, M-1A, M-2, etc.). Cf. L.

12. Brit. motorway (used with a road number to designate a major highway): the M1.

Symbol.

1. the thirteenth in order or in a series, or, when I is omitted, the twelfth.

2. (sometimes l.c.) the Roman numeral for 1000. Cf. Roman numerals.

3. Elect. magnetization.

4. Biochem. methionine.

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      abbreviation of Messier catalog (q.v.), an astronomical listing.

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