In music, sharp, dièse (from French), or diesis (from Greek) means higher in pitch. More specifically, in musical notation, sharp means "higher in pitch by one semitone (half step)". Sharp is the opposite of flat, which is a lowering of pitch. There is an associated sharp symbol which resembles "#", ♯, which may be found in key signatures or as an accidental. For instance, the music below has a key signature with three sharps (indicating either A major or F♯ minor, the relative minor) and the note, A♯, has a sharp accidental. Moreover, under twelve-tone equal temperament, B♯, for instance, sounds...

The ogonek (Polish: [ɔˈɡɔnɛk], "little tail", the diminutive of ogon; Lithuanian: nosinė, "nasal") is a diacritic hook placed under the lower right corner of a vowel in the Latin alphabet used in several European languages, and directly under a vowel in several Native American languages. It is also placed on the lower right corner of consonants in some Latin transcriptions of various indigenous languages of the Caucasus Mountains. An ogonek can also be attached to the top of a vowel in Old Norse-Icelandic to show length or vowel affection. For example, in Old Norse, ǫ represents the Old Norwegian...