joker

the joker in the pack

Someone or something that is unpredictable; a wild card. There are a few unpredictable elements here, but the weather is the real joker in the pack. The joker in the pack in this game will be the performance of the bench players.
See also: joker, pack
Farlex Dictionary of Idioms.

the joker in the pack

mainly BRITISH
If something or someone is the joker in the pack, they are different from the other things or people in a situation and no one knows how they will behave. He's seen very much as the wild boy of Italian fashion — the joker in the pack. Note: The joker in a pack of playing cards is the card which does not belong to any of the four suits.
See also: joker, pack
Collins COBUILD Idioms Dictionary, 3rd ed.

the joker in the pack

a person or factor likely to have an unpredictable effect on events.
In a pack of playing cards, a joker is an extra card which does not belong to one of the four suits (clubs, diamonds, hearts, and spades) and usually bears the figure of a jester. It is used in some card games as a trump and in poker as a wild card.
1973 George Sims Hunters Point Fred Wheeler may be the joker in the pack. He might have got Dave involved in something wild.
See also: joker, pack
Farlex Partner Idioms Dictionary

the ˌjoker in the ˈpack

a person or thing who could change the way that things will happen in a way that cannot be predicted: Everyone knew each other well, except for the new guy Jason, who was the joker in the pack.
The pack here is a set of playing cards. In every pack there are two extra cards, which are called jokers.
See also: joker, pack
Farlex Partner Idioms Dictionary

joker

n. a man; a guy. Who was that joker I saw you with last night?
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions

joker in the deck, a

Any item or device, such as a clause in a contract, that unexpectedly changes the nature of something, either for better or for worse. The noun “joker” alone has been used in this way since the mid-1800s, as in “The postal rate increase had within it a joker that would hurt nonprofit organizations.” Today the term, also put as joker in the pack, sometimes refers to a person whose behavior is unexpected on unpredictable.
See also: joker
The Dictionary of Clichés by Christine Ammer
See also:
  • the joker in the pack
  • now (that) you mention it
  • zeek out
  • quantity
  • unknown
  • unknown quantity
  • an unknown quantity
  • he that would go to sea for pleasure would go to hell for a pastime
  • He that would go to sea for pleasure, would go to hell for a pastime
  • pastime
References in periodicals archive
Overall, Joker is currently positively received according to review aggregatorRotten Tomatoeswith it currently sitting at 87% positive reviews rating it "Fresh".
Joker review roundup: Joaquin Phoenix film is "bold", "twisted", "aggressive" take; The new Joker movie is directed by Todd Phillips and stars Joaquin Phoenix as the iconic villain
For his "final smash," Joker and his group, the "Phantom Thieves of Hearts," launch a coordinated attack on his enemy.
'Super Smash Bros Ultimate' Features 'Persona 5's' Joker
If you can have two Jokers in a deck of playing cards, why can't you have two Jokers in play at your Hollywood table?
Actually, maybe two Joker movies is just fine -- here's why
Joker will take place outside of DC's extended film universe and would help launch a new DC Comics banner at Warner Bros.
Robert De Niro Might Star in the new "Joker" origin film
90cm Speed & Joker: 1 Beri Brown (Lucy); 2 Annie Sandell (Midnight Maelstrom); 3 Zoe Millar (Hank).
Local riders take arena eventing honours; Equestrian
GRINNING MENTALITY Cummings shows off his new Joker smile tattoo
I'LL BE A JOKER IN THE PACK; Squad rookie's a smiling assassin
The untitled Joker and Harley Quinn project is speculated to pave a way for Harley Quinn's solo outing with Gotham City Sirens .
Leonardo DiCaprio the new 'Joker'?
The post Dylan inspires Kyrtis to paint his joker and thief appeared first on Cyprus Mail .
Dylan inspires Kyrtis to paint his joker and thief
Hyundai Card said Tuesday that it has released its promotion app Joker. Based on AR, characters named Joker appear on the screen when a user approaches Hyundai Card-affiliated stores, cafes or cinema complexes.
Financial firms gears up AR promotion
London, United Kingdom, February 19, 2016 --(PR.com)-- For online slots players that also enjoy a little video poker now and then, Slotland (http://www.slotland.eu) has just added a fourth variation on the popular casino game, Deuces & Joker Wild.
Slotland Expands Its Video Poker Collection, Launching New "Deuces & Joker Wild"
Todd Nathan Thompson; THE NATIONAL JOKER; Southern Illinois University Press (Nonfiction: Biography) 29.50 ISBN: 9780809334223
The National Joker; Abraham Lincoln and the Politics of Satire
The National Joker: Abraham Lincoln and the Politics of Satire focuses on an unusual bordering on unique aspect of Abraham Lincoln's presidency--how he used his legendary sense of humor and gift for telling jokes to political ends.
The National Joker
I don't mean to alarm you, but I'm afraid I have a bit of upsetting news: The Joker is bad.
Hegel and the Art of Comic Book Covers
To those who say artist Gerald Skrlin's biting cartoons too often feature Mayor Dyster as the victim of the cartoon skewering, we present "The Joker Goes Green" as a way of spreading the skewering and pointing out the multiple villains in the political circus called Niagara Falls.
Skrlin delivers on the Hamister hotel
JOKER the dog has won a gong after saving the life of his deaf owner's wife when she collapsed in the night.
Pooch Joker saves deaf hubby's wife