1 a person's distinct nature and character, esp. as determined by physical constitution and permanently affecting behaviour (a nervous temperament; the artistic temperament).
2 a creative or spirited personality (was full of temperament).
3 a an adjustment of intervals in tuning a piano etc. so as to fit the scale for use in all keys. b (equal temperament) an adjustment in which the 12 semitones are at equal intervals.
Etymology: ME f. L temperamentum (as TEMPER)
Useful english dictionary. 2012.