According to wikipedia: "Intonation, in music, is a musician's realization of pitch accuracy, or the pitch accuracy of a musical instrument." (https://en.wikipedia.org/wiki/Intonation_(music))
The word "intonation" seems to imply a relationship with "tone", which is often used interchangeably with "timbre" or "tone color". Another definition of tone includes all of "duration, pitch, intensity (or loudness), and timbre (or quality)" together. (https://en.wikipedia.org/wiki/Musical_tone)
Is intonation related to timbre, or any elements of musical tone other than pitch?