co·​star | \ ˈkō-ˌstär \
variants: or co-star
plural costars or co-stars

Definition of costar

 (Entry 1 of 2)

: one of two or more main performers who star in a motion picture, 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


variants: or co-star
costarred or co-starred; costarring or co-starring

Definition of costar (Entry 2 of 2)

1 transitive : to employ or present (someone) as one of two or more leading performers in a motion picture, play, etc. Directed by Lasse Hallström … and costarring a fine ensemble …— Leonora Langley
2 intransitive : to appear with another star in a motion picture, play, etc.

Examples of costar in a Sentence

Recent Examples on the Web: Noun

Smith's chemistry with costar Tommy Lee Jones was a sheer delight, rounded out by an equally terrific cast. Jennifer Ouellette, Ars Technica, "Thor Ragnarok stars reunite, kick alien butt in MiB International trailer," 20 Dec. 2018 The veteran coach, who is infamous for his risky fashion choices, was unfazed by his costar's comment. Kelly O'sullivan, Country Living, "Hear Blake Shelton's Cheeky Response When Carson Daly Asked About Gwen Stefani," 9 Dec. 2018 In addition to Kris Jenner, Grande also had cameos from singer Troye Sivan, Mean Girls' Jonathan Bennett, Legally Blonde's Jennifer Coolidge, and her former Victorious costars Liz Gillies, Matt Bennett, and Daniella Monet. Erica Gonzales, Harper's BAZAAR, "Kris Jenner is Regina George's Mom in Ariana Grande's "Thank U, Next" Music Video," 30 Nov. 2018 Stone and Colman were unable to accept their awards in person, but Weisz arrived onstage accompanied by face cut-outs of her two costars. Lauren Sanchez, Vogue, "The Stars Aligned for Last Night’s Independent Filmmaker Project’s 28th Annual Gotham Awards," 27 Nov. 2018 Reports of a cast feud became so loud, though, that Cattrall's costar Sarah Jessica Parker had to clarify that there's no fight between the two. Julyssa Lopez, Glamour, "This Weird Samantha Plotline Might Be Why Kim Cattrall Passed on Sex and the City 3," 27 Nov. 2018 Jordan's Riverdale costars were quick to congratulate the new fiancé. Carolyn Twersky, Seventeen, ""Riverdale" Star Jordan Connor Just Got Engaged and the Photos are Adorable," 27 Sep. 2018 The actress, 44, stepped out at the world premiere of her upcoming movie Skyscraper in the city with her costar Dwayne Johnson and Feild. Ale Russian,, "Neve Campbell Stuns on Date Night with Boyfriend After Announcing They Adopted a Son," 11 July 2018 Friedle joined his former costars Ben Savage and Danielle Fishel for a panel at New York Comic Con, celebrating the 25th anniversary of their breakout show. Dan Barna, SELF, "'Boy Meets World' Star Will Friedle Says Anxiety Stopped Him From Acting On Camera," 9 Oct. 2018

Recent Examples on the Web: Verb

Along with Capshaw, costars Justin Chambers and Caterina Scorsone are featured in the hilarious gag reel. Karen Mizoguchi,, "Jessica Capshaw Shares Grey’s Anatomy Bloopers Featuring Ellen Pompeo Before Final Episode," 16 May 2018 On April 5, Lynch shared a picture of himself and costar Shipka in character as Harvey and Sabrina on Instagram. Kayleigh Roberts, Marie Claire, "Everything You Need to Know About the New 'Sabrina the Teenage Witch' TV Show," 1 Aug. 2018 Natasha Lyonne costars in Orange Is the New Black, which returns to Netflix this month. Samantha Leach, Glamour, "Read Natasha Lyonne's Love Letter to Her 'Odd Couple' Other Half, Rosie O'Donnell," 26 July 2018 Perhaps the most telling sequence involves Arnold staking out the favorite restaurant of his old True Lies costar, Arnold Schwarzenegger, in the second episode. Todd Vanderwerff, Vox, "The Hunt for the Trump Tapes with Tom Arnold, explained," 18 Sep. 2018 During an Wednesday, August 8 appearance in support of her upcoming film Slender Man, Joey King received a show of support from former Kissing Booth costars Jacob Elordi and Joel Courtney. Lauren Rearick, Teen Vogue, ""The Kissing Booth" Cast Reunited at the Premiere of Joey King's New Movie "Slenderman"," 9 Aug. 2018 Josh Malina is notorious for pranking his Scandal costars — but the tables have turned. Aurelie Corinthios,, "Jimmy Kimmel Pranks Scandal's Josh Malina Ahead of Series Finale — See the Epic Moment," 19 Apr. 2018 Specifically, her salary will now be the same as costars Anthony Hopkins and Ed Harris, who play Dr. Ford and The Man in Black, respectively. Melissa Minton, Glamour, "Evan Rachel Wood Says She'll Receive Equal Pay for 'Westworld' Season 3," 17 Apr. 2018 While Abigail Spencer has worked with plenty of talented people, good friend and former Suits costar Meghan Markle has always stood out. Christina Dugan,, "Timeless Star Abigail Spencer on Her 'Lovely Friend' Meghan Markle," 7 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'costar.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of costar


1888, in the meaning defined above


1896, in the meaning defined above

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Statistics for costar

Last Updated

12 Jan 2019

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Time Traveler for costar

The first known use of costar was in 1888

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Rhyming Dictionary: Words that rhyme with costar

Spanish Central: Translation of costar

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someone who never drinks alcohol

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