blackjack

American  

[blak-jak] / ˈblækˌdʒæk /

noun

1. Cards.

   1. Also called twenty-one.  a gambling game in which the object is to obtain from the dealer cards whose values add up to, or close to, 21 but do not exceed it.

   2. a variety of this game in which any player can become dealer.

   3. Also called natural.  (in the game of blackjack) an ace together with a ten or a face card as the first two cards dealt.

2. a short, leather-covered club, consisting of a heavy head on a flexible handle, used as a weapon.

3. black flag.

4. a small oak, Quercus marilandica, of the eastern United States, having a nearly black bark and a wood of little value except for fuel.

5. a large drinking cup or jug for beer, ale, etc., originally made of leather coated externally with tar.

6. caramel or burnt sugar for coloring spirits, vinegar, coffee, etc.

7. Mineralogy. a dark, iron-rich variety of sphalerite.

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verb (used with object)

1. to strike or beat with a blackjack.

2. to compel by threat.

blackjack ¹ British  

/ ˈblækˌdʒæk /

noun

1. a truncheon of leather-covered lead with a flexible shaft

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verb

1. (tr) to hit with or as if with a blackjack

2. (tr) to compel (a person) by threats

blackjack ² British  

/ ˈblækˌdʒæk /

noun

1. pontoon or any of various similar card games

2. the ace of spades

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blackjack ³ British  

/ ˈblækˌdʒæk /

noun

1. a dark iron-rich variety of the mineral sphalerite

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blackjack ⁴ British  

/ ˈblækˌdʒæk /

noun

1. Also called: blackjack oak.  a small oak tree, Quercus marilandica , of the southeastern US, with blackish bark and fan-shaped leaves

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blackjack ⁵ British  

/ ˈblækˌdʒæk /

noun

1. a tarred leather tankard or jug

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Etymology

Origin of blackjack

First recorded in 1505–15; black + jack ¹

Example Sentences

The best story in “Letters” is the first, in which Ada Blackjack, a young Inupiat woman, is the sole survivor of an ill-fated Arctic expedition begun in 1921.

From The Wall Street Journal • Oct. 10, 2025

Blackjack winners employ a timeless set of strategies: Always assume the dealer’s down card is 10.

From Salon • Jan. 29, 2025

The plant has received state orders to produce a modernized version of the Tu-160 bomber that first flew in the 1980s and was code-named Blackjack by NATO.

From Seattle Times • Feb. 22, 2024

Rotunda came from a family of wrestlers, including his grandfather Blackjack Mulligan, his father Mike Rotunda and his younger brother Bo Dallas.

From BBC • Aug. 25, 2023

Jason and Percy charged each other, but Tempest and Blackjack balked long enough for Piper to leap out of the way.

From "The Mark of Athena" by Rick Riordan