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

After warming up to the theme song from “Top Gun,” he surrendered six hits and struck out just two batters.

From The Wall Street Journal • Mar. 16, 2026

On November 28, Japanese singer Maki Otsuki abandons a performance part-way through the "One Piece" theme song when the music and lights are cut.

From Barron's • Jan. 9, 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

Bernard Herrmann’s orchestra begins to play the Mercury’s theme song, Tchaikovsky’s Piano Concerto no.

From "Spooked!" by Gail Jarrow