fourth(redirected from Perfect fourth)
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Related to Perfect fourth: Perfect fifth
1. denoting the fourth forward ratio of a gearbox in motor vehicles
a. the interval between one note and another four notes away from it counting inclusively along the diatonic scale
b. one of two notes constituting such an interval in relation to the other
3. the fourth forward ratio of a gearbox in a motor vehicle
4. a less common word for quarter