A musical ratio of 16:9 or 9:5.
In classical music from Western culture, a seventh is a musical interval encompassing seven staff positions (see Interval for more details), and the minor seventh is one of two commonly occurring sevenths. It is qualified as minor because it is the smaller of the two: the minor seventh spans ten semitones, the major seventh eleven. For example, the interval from A to G is a minor seventh, as the note G lies ten semitones above A, and there are seven staff positions from A to G. Diminished and augmented sevenths span the same number of staff positions, but consist of a different number of semitones (nine and twelve).
Minor seventh intervals are rarely featured in melodies (and especially in their openings) but occur more often than major sevenths. The best-known example, in part due to its frequent use in theory classes, is found between the first two words of the phrase "There's a place for us" in the song "Somewhere" in West Side Story. Another well-known exception occurs between the first two notes of the introduction to the main theme music from Star Trek: The Original Series theme.