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

We learn that Bacharach composed more than 1,000 pieces of music, including such oddities as the theme song for the cult classic 1958 Steve McQueen thriller “The Blob.”

From The Wall Street Journal • Feb. 5, 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

Gunn’s favorite band Foxy Shazam provides the second season’s theme song, “Oh Lord,” a joyful cacophony of balls-to-the-wall distorted guitar, piano, trumpet blasts and Eric Nally’s energetic tenor vocals.

From Salon • Dec. 14, 2025

Oliver started humming the Star Wars theme song.

From "The Vanderbeekers of 141st Street" by Karina Yan Glaser