Off-key

Off-key is musical content that is not at the expected frequency or pitch period, either with respect to some absolute reference frequency, or in a ratiometric sense (i.e. through removal of exactly one degree of freedom, such as the frequency of a keynote), or pitch intervals not well-defined in the ratio of small whole numbers.

The term may also refer to a person or situation being out of step with what is considered normal or appropriate. A single note deliberately played or sung off-key can be called an "off-note". It is sometimes used the same way as a blue note in jazz.^[1]

^ Sadie, Stanley; Tyrrell, John, eds. (2001). "Off-note". The New Grove Dictionary of Music and Musicians (2nd ed.). London: Macmillan Publishers. ISBN 978-1-56159-239-5.‎ ^{[full citation needed]}

[1] Sadie, Stanley; Tyrrell, John, eds. (2001). "Off-note". The New Grove Dictionary of Music and Musicians (2nd ed.). London: Macmillan Publishers. ISBN 978-1-56159-239-5.‎ ^{[full citation needed]}

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