Pronunciation: [mɪstjˈuːn] (IPA) 
Mistune is spelled with an initial "m" followed by a diphthong "i" (pronounced as /ɪ/ or "ih" sound) and a voiced alveolar stop "st" (/st/ or "st" sound), and ending with a nasal "n" (/n/ or "en" sound). The word means to perform a piece of music or a chord incorrectly during playing. It is important to spell it correctly to avoid confusion with other words with similar spelling, such as "mistaken" or "mistune."
Mistune is a verb that refers to the act of improperly or incorrectly tuning, adjusting, or setting something. It is typically used in relation to musical instruments, specifically when the tuning of a musical instrument is done inaccurately or unsuitably. This can result in the instrument producing an out-of-tune sound that is discordant or dissonant.
The term "mistune" is often used to describe a mistake or error made during the tuning process, whether it be the incorrect application of tension to the strings of a guitar, the misaligning of the keys on a piano, or the improper setting of the reeds on a wind instrument.
Mistuning an instrument can have a significant impact on the quality of sound produced, leading to a lack of harmony or accuracy in pitch. This can be particularly noticeable when playing in ensemble settings or when the instrument is used for performing music, as the notes played may clash with those of other instruments.
While "mistune" typically applies to musical instruments, the term can also be figuratively used in other contexts. For instance, it may be used metaphorically to describe a situation in which someone's actions, decisions, or adjustments result in an outcome that is not as intended or desired. In this way, "mistune" can be understood as the act of misaligning or mismanaging a situation.
To put out of tune; to tune wrongly.
Etymological and pronouncing dictionary of the English language. By Stormonth, James, Phelp, P. H. Published 1874.
