mode

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A manner, way, or method of doing something, experiencing something, or acting: synonym: method.
• noun A particular form or kind.
• noun A given condition of functioning; a status or operation.
• noun The current or customary fashion or style.
• noun Any of certain fixed arrangements of the diatonic tones of an octave, as the major and minor scales of Western music.
• noun A patterned arrangement, as the one characteristic of the music of classical Greece or the medieval Christian Church.
• noun Philosophy The particular appearance, form, or manner in which an underlying substance, or a permanent aspect or attribute of it, is manifested.
• noun The arrangement or order of the propositions in a syllogism according to both quality and quantity.
• noun Statistics The value or item occurring most frequently in a series of observations or statistical data.
• noun Mathematics The number or range of numbers in a set that occurs the most frequently.
• noun Geology The mineral composition of an igneous rock expressed in terms of percentage of the total sample weight or volume.
• noun Physics Any of numerous patterns of wave motion or vibration.
• noun Grammar Mood.

from The Century Dictionary.

• noun A manner of acting or doing; way of performing or effecting anything; method; way.
• noun Customary manner; prevailing style; fashion.
• noun In grammar, the designation, by the form of the verb, of the manner of our conception of an event or fact, whether as certain, contingent, possible, desirable, or the like.
• noun The natural disposition or the manner of existence or action of anything; a form: as, heat is a mode of motion; reflection is a mode of consciousness.
• noun A combination of ideas. See the quotations.
• noun In logic:
• noun A modification or determination of a proposition with reference to possibility and necessity.
• noun A variety of syllogism. See mood, the more usual but less proper form.
• noun The consignificate of a part of speech.
• noun An accidental determination.
• noun In music:
• noun A species or form of scale; a method of dividing the interval of the octave for melodic purposes; an arrangement of tones within an octave at certain fixed intervals from each other.
• noun These modes were embodied in scales of about two octaves, sometimes called transposing scales, which were more or less susceptible of transposition. By the later theorists fifteen such scales were recognized, each derived from one of the foregoing modes, and beginning at adifferent pitch, each a half-step higher than the preceding. These scales, though not always differing from each other in mode, but only in relative pitch, were also called modes, and were named like the modes themselves. Assuming the lowest tone of the lowest scale to be A, the series of later scales or “modes” would be:
• noun Hypodorian, embodying mode IV. above, A.
• noun Hypoionian, Hypoiastian, or lower Hypophrygian (mode V.), B♭.
• noun Hypophrygian (mode V.), B.
• noun Hypoæolian, or lower Hypolydian (mode VI.), C.
• noun Hypolydian (mode VI.), C♮.
• noun Dorian (mode I.), D.
• noun Ionian, Iastian, or lower Phrygian (mode II.), E♭.
• noun Phrygian (mode II.), E.
• noun Æolian, or lower Lydian (mode III.), F.
• noun Lydian (mode III.), F♮.
• noun Hyperdorian, or Mixolydian (mode VII.), G.
• noun Hyperionian, Hyperiastian, or higher Mixolydian (mode VII.), G♮.
• noun Hyperphrygian, or Hypermixolydian (mode VIII.), A.
• noun Hyperæolian, or lower Hyperlydian (mode IX.), B♭.
• noun Hyperlydian (mode IX.), B.
• noun The fact that the term mode has been applied from very early times both to the ideal octave-forms, or true modes, and to the practical scales or tonalities based upon them has led to great confusion. Furthermore, the extant data of the subject are fragmentary and obscure, so that authorities differ widely. (The summary here given is taken chiefly from Alfred Richter.) The esthetic and moral value of the different modes was much discussed by the Greeks, and melodies were written in one or other of the modes according to the sentiment intended to be expressed.
• noun The Gregorian, medieval, or ecclesiastical system was originally intended partly to follow the ancient system. Several of the old modes wore retained, but subsequently received curiously transposed names. The system was initiated by Ambrose, Bishop of Milan, in the latter part of the fourth century, perfected by Gregory the Great about 600, and still further extended between the eleventh and sixteenth centuries. It exercised a deep influence upon the beginnings of modern music, and is still in use in the Roman Catholic Church. The ecclesiastical modes differ from each other both in the relative position of their “finals” or key-notes and in the order of their whole steps and half-steps. They are authentic when the final is the lowest tone of the ambitus or compass, and plagal when it is the fourth tone from the bottom. Four authentic modes were established by Ambrose, the four corresponding plagal modes were added by Gregory, and six others were subsequently appended, making fourteen in all. In each mode certain tones are regarded as specially important — the final, on which every melody must end, and which is nearly equivalent to the modern key-note; the dominant, or principal reciting-note; and the mediant and participant, on which phrases (other than the first and last) may begin and end: these are generically called modulations. All the modes are susceptible of transposition. Assuming the final of the first mode to be A, the full series is as follows (finals are marked F, dominants D,) and mediants M):
• noun *Not used, on account of the tritone between B and F.
• noun In the modern system only two of the historic modes are retained — the major, equivalent to the Greek Lydian and the medieval Ionian, and the minor (in its full form), equivalent to the Greek and medieval Æolian. These modes differ from each other in the order of their whole steps and half-steps, as follows:
• noun See major, minor, and scale.