A qualifier added to descriptions of modes, scales, and intervals, generally indicating that the interval under consideration, (or the charactistic interval of the "3rd" above the "tonic" in the case of a mode or scale), is the smaller of two possibilities, the other possibility being the "major" variant.
There is a distinct qualitative difference in sound and affect between the major and minor variants.
Intervals which come in two basic sizes and must be classified as either "major" or "minor", are categorized as imperfect.
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