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1. Coming next after the eleventh and just before the thirteenth in position
   "For the twelfth time that day her heart turned chill within her";
   - 12th, dozenth

1. Position 12 in a countable series of things
    
2. One part in twelve equal parts
   - one-twelfth, twelfth part, duodecimal

Derived forms: twelfths

See also: ordinal

Type of: common fraction, rank, simple fraction, vulgar fraction [Brit]

Encyclopedia: Twelfth