Pitch variation refers to the changes in the musical tones used in vocal or instrumental performances. Alternative phrases that can be used interchangeably with pitch variation include pitch modulation, tonal inflection, and variation in sound frequency. Other synonyms include intonation, melodic variation, and sound variation. Furthermore, terms such as pitch shift, pitch deviation, and pitch fluctuation can also be used to refer to variations in musical tones, but can have different connotations in various contexts. In linguistic contexts, pitch accent and tone may refer to pitch variation in speech. All these terms are commonly used to describe the variations in pitch that create melodic interest and emotion in music and speech.