tonality, in music, quality by which all tones of a composition
are heard in relation to a central tone called the keynote or
tonic. In music that has harmony the terms key and tonality are
practically synonymous, embracing a hierarchy of constituent
chords, and a hierarchy of related keys. Some relationship to a
tonic is characteristic of all music except that in which it is
deliberately avoided (see atonality and serial music). The term
tonality is also used in contrast to modality (see mode).
Organization of music around a single pitch; more specifically,
the Western system of keys that grew out of the modal music of
the Renaissance in the 17th century. The term is often used to
refer to the network of relationships implicit in the seven
principal tones of a given key, each of which has the potential
to become the tonic temporarily by means of modulation, whereby
a new network of relationships arises. Because of its capacity
to extend pitch relationships to remote lengths in an audibly
comprehensible way,