theme song

American  

noun

1. a melody in an operetta or musical comedy so emphasized by repetition as to dominate the presentation.

2. a melody identifying or identified with a radio or television program, dance band, etc., usually played at the beginning of each program.

3. an expression, comment, or subject of conversation that a person or group uses habitually.

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theme song British  

noun

1. a melody used, esp in a film score, to set a mood, introduce a character, etc

2. another term for signature tune

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Etymology

Origin of theme song

An Americanism dating back to 1925–30

Example Sentences

It completely made sense to me, like the theme song being, “Thank you for being a friend,” and it’s her only friend.

From The Wall Street Journal

He still records music for his productions, including a theme song for his upcoming TV series “Fightland,” a boxing drama filmed in London.

From The Wall Street Journal

As the film prepares to open, Franglen is celebrating a Golden Globe nomination for the theme song, Dream As One, sung by Miley Cyrus.

From BBC

In September, Pokémon said it did not give permission for the use of its theme song and other footage to be used in an ICE deportation raid video posted by the US government.

From BBC

Rams defensive end Kobie Turner is a musical wiz, and he showed it by playing the theme song to NBC’s “Sunday Night Football.”

From Los Angeles Times