An
equal temperament is a
musical temperament, or a system of
tuning, in which every pair of adjacent pitches is separated by the same
interval. In other words, the pitches of an equal temperament can be produced by repeating a generating interval. Equal intervals also means equal ratios between the
frequencies of any adjacent pair, and, since
pitch is perceived roughly as the
logarithm of frequency, equal perceived "distance" from every note to its nearest neighbor.