alto clef

For other senses of this word, see clef (disambiguation). A clef (from the French for "key") is a musical symbol used to indicate the pitch of written notes.* Placed on one of the lines at the beginning of the staff, it indicates the name and pitch of the notes on that line. This line serves as a reference point by which the names of the notes on any other line or space of the staff may be determined.
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Noun
1. a clef that puts middle C on the third line of a staff
(synonym) viola clef
(hypernym) clef

CHIAVE DI CONTRALTO

n. ดนตรีตัว C บนเส้นเสียงที่สามของเครื่องดนตรี