Unequal temperament

Temperament Tem"per*a*ment, n. [L. temperamentum a mixing in due proportion, proper measure, temperament: cf. F. temp['e]rament. See {Temper}, v. t.] 1. Internal constitution; state with respect to the relative proportion of different qualities, or constituent parts. [1913 Webster]

The common law . . . has reduced the kingdom to its just state and temperament. --Sir M. Hale. [1913 Webster]

2. Due mixture of qualities; a condition brought about by mutual compromises or concessions. [Obs.] [1913 Webster]

However, I forejudge not any probable expedient, any temperament that can be found in things of this nature, so disputable on their side. --Milton. [1913 Webster]

3. The act of tempering or modifying; adjustment, as of clashing rules, interests, passions, or the like; also, the means by which such adjustment is effected. [1913 Webster]

Wholesome temperaments of the rashness of popular assemblies. --Sir J. Mackintosh. [1913 Webster]

4. Condition with regard to heat or cold; temperature. [Obs.] [1913 Webster]

Bodies are denominated ``hot'' and ``cold'' in proportion to the present temperament of that part of our body to which they are applied. --Locke. [1913 Webster]

5. (Mus.) A system of compromises in the tuning of organs, pianofortes, and the like, whereby the tones generated with the vibrations of a ground tone are mutually modified and in part canceled, until their number reduced to the actual practicable scale of twelve tones to the octave. This scale, although in so far artificial, is yet closely suggestive of its origin in nature, and this system of tuning, although not mathematically true, yet satisfies the ear, while it has the convenience that the same twelve fixed tones answer for every key or scale, C[sharp] becoming identical with D[flat], and so on. [1913 Webster]

6. (Physiol.) The peculiar physical and mental character of an individual, in olden times erroneously supposed to be due to individual variation in the relations and proportions of the constituent parts of the body, especially of the fluids, as the bile, blood, lymph, etc. Hence the phrases, bilious or choleric temperament, sanguine temperament, etc., implying a predominance of one of these fluids and a corresponding influence on the temperament. [1913 Webster]

{Equal temperament} (Mus.), that in which the variations from mathematically true pitch are distributed among all the keys alike.

{Unequal temperament} (Mus.), that in which the variations are thrown into the keys least used. [1913 Webster]