costar

1 of 2

noun

co·​star ˈkō-ˌstär 

variants or co-star

plural costars or co-stars

: one of two or more main performers who star in a movie, play, etc.

… the star seems more relaxed and confident, and there's a bracing snap to the byplay between him and his costars.

—Mark Harris

costar

2 of 2

verb

variants or co-star

costarred or co-starred; costarring or co-starring

1

transitive : to employ or present (someone) as one of two or more leading performers in a movie, play, etc.

Directed by Lasse Hallström … and costarring a fine ensemble …

—Leonora Langley

2

intransitive : to appear with another star in a movie, play, etc.

Examples of costar in a Sentence

Recent Examples on the Web

Noun

Original costar Rosa Salazar then dropped out of the series, with Fumero stepping into her role. —Joe Otterson, Variety, 24 Mar. 2026

The iconic 1968 Camaro SS convertible, equipped with a 502-cubic-inch GM performance crate motor and approximately 502 horsepower, became a legitimate costar, with its own trailer in which it’s ferried to filming locations across the country. —Terry Baddoo, USA Today, 23 Mar. 2026

Verb

Connections were made in the Dolby lobby bar where Bugonia costars Emma Stone and Alicia Silverstone reunited. —Shania Russell, Entertainment Weekly, 16 Mar. 2026

The film costars Chris Hemsworth, Monica Barbaro, Mark Ruffalo and Barry Keoghan. —Julia Teti, Footwear News, 3 Feb. 2026

Word History

First Known Use

Noun

1888, in the meaning defined above

Verb

1896, in the meaning defined at sense 2