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

The Show was created on the fly, based around a drum loop and the theme song to kids' TV show Inspector Gadget.

From BBC • Mar. 25, 2026

The boy said he was trying to think of happy things, at one point singing the "Thomas the Tank Engine" theme song.

From Barron's • Feb. 3, 2026

A typical night can seamlessly bounce from CupcakKe to Robyn, Chappell Roan to Beyoncé and Lady Gaga’s aughts banger “Telephone,” and also “Rivalry,” the show’s theme song by Peter Peter.

From Los Angeles Times • Jan. 18, 2026

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 • Dec. 14, 2025

And this, this, the gotta catch from Axel’s very favorite theme song, finally brings on the smile that Daniel’d been waiting to see.

From "A Bird Will Soar" by Alison Green Myers