Discant or descant (, meaning "singing apart") originated as a style of liturgical setting in the Middle Ages, associated with the development of the Notre Dame school of polyphony. In origin, it is a style of organum that either includes a plainchant tenor part (usually on a melisma in the chant) or is used without a plainchant basis in conductus, in either case with a "note against note" upper voice, moving in contrary motion. It is not a musical form, but rather a technique. The term continued to be used down to modern times with changing senses, at first for polyphony in general, then to differentiate a subcategory of polyphony (either in contrast to organum, or for improvised as distinct from written polyphony). By extension it became the name of a part that is added above the tenor, and later as the name of the highest part in a polyphonic setting (the equivalent of "cantus", "superius", and "soprano"). Finally, it was adopted as the name of the highest register of instruments such as recorders, cornets, viols, and organ stops. "English discant is three-voice parallelism in first-inversion triads." However, because it allowed only three, four, or at most five such chords in succession, emphasizing contrary motion as the basic condition, it "did not differ from the general European discant tradition of the time". Because English discant technique has commonly been associated with such a succession of first-inversion triads, it has inevitably become confused with fauxbourdon, with which it has "no connection whatsoever". This misinterpretation was first brought forward in 1936 by Manfred F. Bukofzer, but has been proved invalid, first in 1937 by Thrasybulos Georgiades, and then by Sylvia Kenney and Ernest Sanders. A second hypothesis, that an unwritten tradition of this kind of parallel discant existed in England before 1500, "is supported neither by factual evidence nor by probability".