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’s theme song, which has been updated for the new series, remains popular on TikTok among teens who first watched the show as preschoolers.

From Los Angeles Times • May 22, 2026

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

“Have you had enough?” asks the rusty-razor theme song to “Young Sherlock.”

From The Wall Street Journal • Mar. 3, 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

Then Fairuz, the beloved Lebanese singer, wailed the show’s theme song.

From "Tasting the Sky" by Ibtisam Barakat