Related Clues:

• IOU, e.g.
• Middle C, e.g.
• '___ to self . . .'
• Staff member
• Symbol on a staff
• Jot down
• Musical staff symbol
• Part of a melody
• Write down quickly
• It can be flat
• A, for one
• Pay heed to
• Bear in mind
• Something to pass in school
• Brief memo