An inherent or distinguishing characteristic; a property. A personal trait, especially a character trait: "The most vital quality a soldier can possess is self-confidence\u201d ( George S. Patton). Essential character; nature: "The quality of mercy is not strain'd\u201d ( Shakespeare). Superiority of kind: an intellect of unquestioned quality. Degree or grade of excellence: yard goods of low quality. High social position. Those in a high social position. Music Timbre, as determined by harmonics: a voice with a distinctive metallic quality. Linguistics The character of a vowel sound determined by the size and shape of the oral cavity and the amount of resonance with which the sound is produced. Logic The positive or negative character of a proposition. Having a high degree of excellence: the importance of quality health care.