co·​star | \ ˈkō-ˌstär How to pronounce costar (audio) \
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 The Batman costar Robert Pattinson, who will take on the role of the Caped Crusader when the movie opens in October 2021. Dana Rose Falcone,, "Zoë Kravitz Says She’s Making ‘Less Bad Choices’ After Getting Married: ‘I Would Like to Think’," 26 June 2020 Well then, Stitcher has an offer for you: The podcast producer will drop a new one Thursday featuring the actor, and EW has an exclusive clip from the first episode with Lowe's Parks and Recreation costar Chris Pratt (listen above). Ew Staff,, "Listen to Rob Lowe and Chris Pratt bond over beloved TV shows in exclusive clip from Literally! podcast," 24 June 2020 Clarkson has reportedly been leaning on celebrity friends, like her Voice costar Blake Shelton and country singer Reba McEntire—even though both also have close ties to Blackstock. Abby Gardner, Glamour, "Kelly Clarkson Has Reportedly Been Leaning on These Two Celeb Friends Amid Her Divorce," 18 June 2020 Jamie-Lynn Sigler costar in this cliched 2019 crime drama set in the 1950s. Matt Cooper, Los Angeles Times, "What’s on TV This Week: A Bruce Lee doc on ESPN and more," 5 June 2020 On Monday, 9-1-1 actress Aisha Hinds joined Oliver Stark in speaking out against their costar Ryan Guzman's defense of using racial slurs. Ruth Kinane,, "9-1-1 castmates slam Ryan Guzman's defense of using racial slurs," 1 June 2020 Before White, Dobrev was linked to actor Glen Powell, and previously dated her Vampire Diaries costar Ian Somerhalder for three years. Kathryn Lindsay,, "It Looks Like Nina Dobrev Is Dating This Very Famous Former Olympian," 30 May 2020 Tomlin’s wedding cameo comes days after the actress fulfilled her promise to get arrested as part of friend and costar Jane Fonda’s Fire Drill Fridays climate change protest. Christi Carras, Los Angeles Times, "Kathy Griffin is now married, thanks to Lily Tomlin," 2 Jan. 2020 Let Kit Harington's loving words about his costars fill the House Stark-sized hole in your heart. Erica Gonzales, Harper's BAZAAR, "Kit Harington Gushes over Sophie Turner: "I Love That Girl to My Very Bones"," 14 Oct. 2019 Recent Examples on the Web: Verb In 2012, Howard was nominated for an NAACP Image Award for outstanding supporting actress for The Help, a trophy that ultimately went to costar Octavia Spencer. Benjamin Vanhoose,, "Bryce Dallas Howard Urges Fans to 'Go Further' Than The Help in Understanding Racism," 8 June 2020 Here's the clip, which costars Darrell Hammond: Fallon's SNL sketch has been periodically resurfaced and criticized, but this might have been the first time the talk show host has addressed it. James Hibberd,, "Jimmy Fallon apologizes for wearing blackface in resurfaced SNL clip," 26 May 2020 Rose Byrne costars as the animals’ human friend, Bea, a character modeled on Potter. Los Angeles Times, "What’s on TV Friday, April 17: MacGyver on CBS; Coronavirus," 16 Apr. 2020 Upon being shown a picture of herself at her Game of Thrones costars Kit Harington and Rose Leslie's wedding in June 2018, Turner actually groaned. Kayleigh Roberts, Marie Claire, "Sophie Turner Says the Outfit She Wore to Kit Harington's Wedding Is One of Her Worst Looks Ever," 7 Mar. 2020 Producer Eric Andre costars in the project, which will hit theaters nationwide. Ariana Marsh, Harper's BAZAAR, "The Best Documentaries of 2020 That Have Been Announced So Far," 6 Feb. 2020 Billy Porter also costars as Barrett, the man who produces their cosmetics, but the part leans too heavily on gay stereotypes pulled from another decade. Maureen Lee Lenker,, "Like a Boss is a female buddy comedy in need of a serious makeover: Review," 9 Jan. 2020 Henry Golding costars as Emily's author husband, impossibly dashing and possibly duplicitous. Isaac Feldberg, Fortune, "What to watch on Amazon Prime while social distancing during the coronavirus pandemic," 27 Mar. 2020 Aniston is currently promoting her new Apple TV+ series, The Morning Show, which costars Reese Witherspoon. Amy Mackelden, Harper's BAZAAR, "Jennifer Aniston Just Wore a Strapless Black Dress in the Rain," 30 Oct. 2019

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 at sense 2

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Time Traveler for costar

Time Traveler

The first known use of costar was in 1888

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Statistics for costar

Last Updated

2 Jul 2020

Cite this Entry

“Costar.” Dictionary, Merriam-Webster, Accessed 3 Jul. 2020.

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More Definitions for costar


How to pronounce costar (audio)

English Language Learners Definition of costar

: one of two or more main actors in a movie, television show, or play

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More from Merriam-Webster on costar

Thesaurus: All synonyms and antonyms for costar

Rhyming Dictionary: Words that rhyme with costar

Spanish Central: Translation of costar

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