tune

• melody; state of having the correct musical pitch; harmony; proper adjustment
adjust to obtain correct musical pitch; adjust to improve operation (e.g. a car engine); adjust to obtain operational conditions (e.g. radio frequency); coordinate, make harmonious; make a musical sound; adjust to a different goal or framework
a tune is a series of musical notes that is pleasing or memorable. a tune sometimes occurs repeatedly in a piece of music.
you can also refer to a song or a short musical piece as a tune.
when someone tunes a musical instrument, they adjust it so that it produces the right notes.
when someone tunes an engine or machine, they adjust it so that it works well.
if your radio or television is tuned to a particular broadcasting station, it has been adjusted so that you can listen to or watch the programmes on that station.
if you say that a particular person is the one who calls the tune, you mean that this person has authority and says what is to be done.
if you play or sing in tune, you are playing or singing exactly the right notes. if you play or sing out of tune, you are playing or singing notes that are not quite right.
if you are in tune with someone or something, you are in agreement with them or understand them well.
if you change your tune, you say or do something different from what you previously said or did.
to the tune of a particular amount means to the extent of that amount; a formal expression.
if you tune in to a radio station, you adjust your radio so that you can listen to it.
to tune out a radio or television broadcast means to stop listening to the broadcast by changing or cutting out the radio signals.
if you tune someone or something out, you stop listening to them or paying attention to them.
when a group of musicians tune up, they adjust their instruments so that they produce the right notes exactly.