1. One of four playing cards in a deck having a single pip on its face
   "He drew the ace of spades from the deck"
    
2. [informal] Someone who is dazzlingly skilled in any field
   "She's a real tech ace, always up-to-date with the latest gadgets";
   - adept, champion, sensation, maven [US, informal], mavin [US, informal], virtuoso, genius, hotshot [informal], star, superstar, whiz [informal], whizz [informal], wizard [informal], wiz [informal], megastar [informal]
    
3. A serve that the receiver is unable to reach
   "The tennis player won the match with an ace on match point"

1. Of the highest quality, skill, etc.; very good or impressive
   "an ace reporter";
   - A-one [informal], crack [informal], first-rate, super, tiptop, topnotch [informal], top-notch [informal], tops [informal], A1 [informal], top-class, gnarly [N. Amer, informal], excellent, first-class, fantabulous [informal], splendid, ripping [Brit, archaic, informal], mean [informal], outstanding, lush [Brit, informal], brilliant, beezer [UK, archaic], stellar [informal], awesome [informal], top-drawer, dope [N. Amer, informal], socko [N. Amer, informal], righteous [US, slang], fab [Brit, informal], crucial [slang], rad [N. Amer, slang], radical [N. Amer, slang], nang [Brit, slang], phat [slang], legit [US, slang], awesomesauce [informal], amazeballs [informal], beaut [Austral, NZ, informal], lit [US, slang], storming [Brit, informal], blinding [Brit, slang], stonking [Brit, informal], brill [Brit, informal], wicked [slang], cushty [Brit, informal], def [slang], magic [Brit, slang], smokin' [slang], smoking [slang], sick [N. Amer, slang]

1. Succeed decisively or with distinction
   "She aced the exam without any preparation";
   - breeze through [informal], pass with flying colors [US], sweep through, sail through, nail [informal], pass with flying colours [Brit, Cdn]
    
2. (tennis) serve an ace against (someone)
   "She aced her opponent three times in the final set"
    
3. Score an ace against
   "He aced his opponents"
    
4. (golf) play (a hole) in one stroke
   "He aced the par-3 seventh hole"

1. Proteolytic enzyme that converts angiotensin I into angiotensin II
   "ACE inhibitors block the angiotensin converting enzyme to lower blood pressure";
   - angiotensin converting enzyme, angiotensin-converting enzyme
    
2. A major strategic headquarters of NATO safeguarding an area extending from Norway to Turkey
   - Allied Command Europe

Derived forms: aced, aces, acing

See also: breeze [informal], super-duper [informal], superior

Type of: expert, headquarters, make it, make the grade [N. Amer], pass, peptidase, play, playing card, protease, proteinase, proteolytic enzyme, rack up, score, serve, service, tally

Part of: NATO, North Atlantic Treaty Organisation [Brit], North Atlantic Treaty Organization

Encyclopedia: Ace, TX