Определение ledger line в Английский Язык Английский Язык словарь
A musical notation to inscribe notes outside the lines and spaces of the regular musical staffs; a line slightly longer than the note is drawn parallel to the staff, above or below, spaced at the same distances as the notes within the staff
n. Music A short line placed above or below a staff to accommodate notes higher or lower than the range of the staff. a line on which you write musical notes that are too high or low to be shown on a stave