High Quality Content by WIKIPEDIA articles! Off-key is a term often used to denote 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.