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 Wheel of Fortune theme song starts playing when she plugs it back in, but the picture on the cracked screen is fuzzy static.

From Literature

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

From Barron's

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

The plot and the stirring theme song remind me why I’ve always loved living and working in New York, and how the energy of the big city is my engine.

From The Wall Street Journal

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