noun (1)
\ ˈās How to pronounce ace (audio) \

Definition of ace

 (Entry 1 of 7)

1a : a die face marked with one spot
b : a playing card marked in its center with one pip
c : a domino end marked with one spot
2 : a very small amount or degree : particle
3 : a point scored especially on a service (as in tennis or handball) that an opponent fails to touch
4 : a golf score of one stroke on a hole also : a hole made in one stroke
5 : a combat pilot who has brought down at least five enemy airplanes
6a : a person who excels at something a computer ace
b : the best pitcher on a baseball team the ace of the staff
ace in the hole
1 : an ace dealt face down to a player (as in stud poker) and not exposed until the showdown
2 : an effective and decisive argument or resource held in reserve
within an ace of
: on the point of : very near to came within an ace of winning


aced; acing

Definition of ace (Entry 2 of 7)

transitive verb

1 : to score an ace against (an opponent)
2 : to make (a hole in golf) in one stroke
3 : to gain a decisive advantage over : defeat usually used with out
4a : to earn a high grade on (something, such as an examination) especially : to get an A on
b : to perform extremely well in he aced every subject


adjective (1)

Definition of ace (Entry 3 of 7)

: of first or high rank or quality an ace mechanic


adjective (2)

Definition of ace (Entry 4 of 7)

: asexual But ace individuals often still feel romantic attraction toward others, as well as a drive to cultivate intimate, loving relationships—just without an intrinsic interest in pursuing the sexual aspect.— Taryn Deoilers


noun (2)
plural aces

Definition of ace (Entry 5 of 7)

: an asexual person (see asexual sense 3b) Like many other aces and aros, I grew up thinking I was broken. I was 19 before I heard the words "asexual" or "aromantic," before I found out that there were other people in the world like me.— Mikayla Micomonaco



Definition of Ace (Entry 6 of 7)

used for a bandage with elastic properties

Definition of ACE (Entry 7 of 7)

1 American Council on Education
2 \ ˌā-​(ˌ)sē-​ˈē How to pronounce ˌā-(ˌ)sē-ˈē (audio) , ˈās-​ \ angiotensin converting enzyme The ACE inhibitors are designer molecules developed specifically to attach to their target enzyme and prevent it from activating angiotensin. Virtually the only thing these drugs do in the body is to interact with ACE. However, ACE is not a very specific enzyme; it acts on hormones besides angiotensin.Harvard Medical Health Letter

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Examples of ace in a Sentence

Noun (1)

She won the match by scoring more than 30 aces. took a few lessons with a tennis ace to improve his backhand


She aced her entrance exams. He aced his annual physical. He aced his opponent on the last point of the match.
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Recent Examples on the Web: Noun

Over/under: Take the UNDER (9.5, -105) with Means having emerged as the ace of the Orioles’ staff and Stripling enjoying a phenomenal second half as a key swingman. Esten Mclaren, USA TODAY Sportsbook Wire, "Los Angeles Dodgers at Baltimore Orioles odds, picks and betting tips," 11 Sep. 2019 Leading the way for the Broncos was Skyler Wagner with 11 kills, 4 solo blocks, 3 assisted blocks and added 4 aces at the service line. David Taylor, Houston Chronicle, "Roundups: Liberty County sports shorts," 10 Sep. 2019 Sophia Maniaci added four service aces for Costa Mesa (10-7). Daily Pilot, "High School Roundup: Corona del Mar girls’ tennis wins season opener," 3 Sep. 2019 Kailee Rodrigues totaled 15 assists and Lexie Vanderpol added 11 aces in the win. Charlie Wolfson,, "No. 2 St. John’s Prep blanks Masconomet in boys’ soccer opener," 3 Sep. 2019 Keys hit 13 aces in the match to finish with a total of 59 for the week, which tied a career high. Ben Rothenberg, New York Times, "Madison Keys Wins Western & Southern, but Keeps Eyes on U.S. Open," 18 Aug. 2019 This is not the same Jhoulys Chacín who was the de facto ace of the Milwaukee Brewers starting rotation in 2018. Tom Haudricourt, Milwaukee Journal Sentinel, "Diamondbacks 10, Brewers 7: Jhoulys Chacín's lost season continues with short, ugly outing," 20 July 2019 Before the season, he was named the ace of the staff. Sam Blum |,, "Injured Auburn ace Davis Daniel opens up about missing season," 6 June 2019 The 6-foot-10 American hit 21 aces in the semifinal and has 98 in five tournament matches. Steven Wine, The Seattle Times, "Federer, defending champ Isner to meet in Miami Open final," 30 Mar. 2019

Recent Examples on the Web: Verb

The set got off to an inauspicious start for Bouchard, who was aced as Townsend’s first left-handed serve twisted away from her. Matt Szabo, Daily Pilot, "Orange County Breakers outlast Philadelphia Freedoms, move into three-way tie for third in World Team Tennis," 23 July 2019 But a single good night can repair some of the damage: People who slept more than usual the night before they were tested ended up acing more of the cognitive tests. Susan Pinker, WSJ, "When It Comes to Sleep, One Size Fits All," 25 Oct. 2018 SpaceX’s first prototype for its Mars-colonizing Starship vehicle aced its final test flight today (Aug. 27), rising several hundred feet off the ground at the company’s facility in the tiny South Texas town of Boca Chica. Mike Wall, Scientific American, "SpaceX Starhopper Rocket Prototype Aces Highest (and Final) Test Flight," 28 Aug. 2019 A few minutes later, Jones aced UTSA’s catching gantlet, hauling in seven passes from alternating directions during a sprint across the field. Greg Luca,, "Sheldon ‘Sticks’ Jones brings energy to UTSA wide receivers group," 7 Aug. 2019 If so, the young Chicago artist aced his audition on the big stage. Greg Kot,, "Pitchfork Music Fest 2019: 3 days of heat, rain and music rich in cultural diversity," 22 July 2019 In that respect, the two-way player from last season's roster aced his test, closing with 26 points, eight rebounds, three assists and three steals in the game that ultimately ended the Heat's 6-2 summer run. Ira Winderman,, "Duncan Robinson now in the bonus round for the Heat," 14 July 2019 Prince George is already acing his tennis skills — with the help of a pro. Stephanie Petit,, "Kate Middleton Says Prince George Has Played Tennis with His Favorite Player, Roger Federer!," 3 July 2019 The twins aced their classes, and graduated high school sharing the coveted title of valedictorian. CBS News, "Immigrant twins who picked grapes in California graduate from medical school one day apart," 15 June 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ace.' 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 ace

Noun (1)

14th century, in the meaning defined at sense 1a


1923, in the meaning defined at sense 1

Adjective (1)

1926, in the meaning defined above

Adjective (2)

2009, in the meaning defined above

Noun (2)

2008, in the meaning defined above

History and Etymology for ace

Noun (1)

Middle English as, borrowed from Anglo-French, going back to Latin ass-, ās "copper money piece (at first a pound, but progressively reduced to a half-ounce), pound unit of weight, unit," of uncertain origin

Note: The word ās has been compared within Latin to asser "wooden beam, pole, post" (generalized from a plural asserēs, from a singular *assis?) and assis, axis (by hypercorrection?) "plank, board," though any relationship is far from certain. A loanword from Etruscan?

Adjective (1)

derivative of ace entry 1

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Learn More about ace

Dictionary Entries near ace


accustom oneself to






Statistics for ace

Last Updated

7 Oct 2019

Look-up Popularity

Time Traveler for ace

The first known use of ace was in the 14th century

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More Definitions for ace



English Language Learners Definition of ace

US, informal : to earn a very high grade on (an examination) : to get a grade of A on (an examination) : to perform very well on (a test or challenge)
: to score an ace against (an opponent in tennis)
US : to score an ace on (a hole in golf)


\ ˈās How to pronounce ace (audio) \

Kids Definition of ace

 (Entry 1 of 2)

1 : a playing card with one figure in its center
2 : expert entry 2 a flying ace



Kids Definition of ace (Entry 2 of 2)

: of the very best kind an ace reporter


\ ˈās How to pronounce Ace (audio) \

Medical Definition of Ace

 (Entry 1 of 2)

used for a bandage with elastic properties

Medical Definition of ACE (Entry 2 of 2)

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More from Merriam-Webster on ace

Rhyming Dictionary: Words that rhyme with ace

Thesaurus: All synonyms and antonyms for ace

Spanish Central: Translation of ace

Nglish: Translation of ace for Spanish Speakers

Britannica English: Translation of ace for Arabic Speakers

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