noun

• A person who tunes a piano or organ.
• A device, electronic or mechanical, that helps a person tune a musical instrument by showing the deviation of the played pitch from the desired pitch.
• On a musical instrument, a peg or mechanical device that changes the tension, and hence pitch, of a string.
• The component of an audio system that receives radio broadcasts.
• (archaic) One who sings or makes music.
• (entertainment industry, informal) A musical.