keyboard

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A set of keys, as on a computer terminal, word processor, typewriter, or piano.
2. n. Music A piano.
3. n. Music Any of various instruments, played by means of a set of pianolike keys, often connected to a synthesizer or amplifier.
4. v. To set (copy) by means of a keyed typesetting machine: keyboard a manuscript.
5. v. To enter (text or data) into a computer by means of a keyboard.
6. v. Music To play (a composition) on a piano or keyboard.

Century Dictionary and Cyclopedia

1. n. In the organ, pianoforte, and similar instruments, as the harpsichord, clavichord, etc., the series or horizontal row of finger-levers or digitals (usually called keys), by depressing which the performer causes the pipes, strings, or reeds to produce tonos. The visible portions of part of the keys are white, while the others are black. The black keys are the shorter, and are raised above the level of the white keys; they are always separated from one another by one or two white keys, so as to form groups alternately of two and three. The depression of which the keys are capable is technically called the “dip.” The keyboard contains altogether from fifty to ninety keys, the ratio of white to black being 7.5. The right-hand end of the keyboard is called the upper, because the keys there produce high tones, and the left-hand end is correspondingly called the lower. The white key next below (to the left of) the upper key of every group of three black keys is called A; the next white key to the right of this is called B; the next is called C; and so on, up to G, next to which another A is found. In Germany, by a curious difference of nomenclature, B is always called H, and B♭ is called B. (See B quadratum and B rotundum, under B.) In tuning, the tones produced by the various keys called by the same letter-name are made exact octaves of each other. The black keys are named by reference to the white keys on either side of them: thus, the black key between A and B is either A♮ or B♭, that between C and D is either C♮ or D♭, etc. When a white key is to be specially distinguished from a black one, it is called a natural: hence a scale or series of tones produced by using only white keys is called the natural scale, and its key (tonality) is called the natural key. (See key.) In general, a key next on the right to any given key is the sharp of the latter, and the second key to the right is its double sharp; while a key next on the left to any given key is the flat of the latter, and the second key to the left is its double flat. Thus, every key on the keyboard, except the black key called either G♯ or A♭, has three names : as A = Gx = B♭♭, B = Ax = C♭, C = B♯ = D♭♭ etc.; A♯ = B♭ = C♭♭, C♯ = D♭ = Bx, etc. (See flat and sharp.) The several keys and octaves are usually calculated from middle C —the C nearest the center of the keyboard, and historically the middle tone of the medieval hexachord system (see hexachord) —the vibration-number of whose tone is theoretically from 250 to 265. (See C.) The keyboard of the organ usually extends four to five octaves, from the second C below middle C to the third A or C above middle C; that of the pianoforte usually extends six to seven or seven and a third octaves, from the third A below middle C to the fourth A or C above middle C. The organ usually has keyboards both for the hands and for the feet, the former being distinguished as manual keyboards or manuals, the latter as pedal keyboards or pedals; and there are usually two or more manual keyboards, each with its own sets of pipes or stops, and capable of being used either independently or in conjunction with the others. The principal keyboard is that of the great organ; that above it is that of the swell organ; that below it (when there are three), that of the choir organ. (See organ.) In the old harpsichords and similar instruments two keyboards were sometimes provided, the one producing tones of different quality or force from the other. The keyboard has been developed gradually. Its first appearance was about the end of the eleventh century, when large levers that could be manipulated only by the whole hand or a blow of the fist, having a dip of several inches or even a foot, were introduced into the organ, and later into the clavichord and similar instruments. Only the levers corresponding to the modern white keys (diatonics) were used at first; those corresponding to the modern black keys (chromatics) were introduced in the twelfth to the fourteenth century, probably in this order: B♭, F♯, C♯, E♭, G♯ The chromatics were first placed in a distinct row from the diatonics; but iu the fifteenth century all were combined into a single keyboard. The pedal keyboard was invented for the organ about the same time. Until the close of the eighteenth century the keys were colored white and black in exactly reverse order from the modern custom. (For a description of the mechanical details of the keyboard, see organ and pianoforte.) The gradual development of the keyboard kept pace with the gradual unfolding of the theory of the musical scale and of tonality. (See temperament.) To avoid the inaccuracy of many of the intervals in equal temperament, keyboards with more than twelve digitals and tones to the octave have been devised, but their use has been principally confined to acoustical investigations. The mechanical manipulation of the keyboard in musical performance involves a thorough muscular discipline of the hands. See touch, fingering, technique.
2. n. Pedal keyboards in the organ are called radiating when the keys are made to converge somewhat below the player's seat, like the ribs of a fan, and concave when the general level of the inner keys is lower than that of the outer ones. In the best organs the pedal keyboard is both concave and radiating.
3. n. The set of keys for operating the letters of a type-writing or type-settingmachine.

Wiktionary

1. n. A set of keys used to operate a typewriter, computer etc.
2. n. music A component of many instruments including the piano, organ, and harpsichord consisting of usually black and white keys that cause different tones to be produced when struck.
3. n. music A device with keys of a musical keyboard, used to control electronic sound-producing devices which may be built into or separate from the keyboard device.
4. v. intransitive To type on a computer keyboard.

GNU Webster's 1913

1. n. The whole arrangement, or one range, of the keys{3} of an organ, piano, typewriter, etc.; that part of a device containing the keys{3} used to operate it.

WordNet 3.0

1. n. device consisting of a set of keys on a piano or organ or typewriter or typesetting machine or computer or the like
2. n. holder consisting of an arrangement of hooks on which keys or locks can be hung