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D. See double down.

D2. Acronym for "double down on any first 2 cards."  See Da. See D2.  See DOA.

D3. Acronym for "double down on 3 or more cards."

D8. Acronym for "double down on 8, 9, 10, 11 only."

D9. Acronym for "double down on 9, 10, 11 only."

D10. Acronym for "double down on 10 and 11 only."

D11. Acronym for "double down on 11 only."

DA. Acronym for "double down on any first two cards."   See D2. See Da. See DOA.

DA2. Acronym for "double down on any first two cards."  See Da.  See D2. See DOA.

DACE. Acronym for "double down but not hit after splitting aces".  See DSA.

Dakota. Legal low limit games were available at several locations in North and South Dakota at time of writing.
[82 Ristvedt The North Dakota Blackjack Book]

Dakota Rules. TBD

D'Alembert. {PBS} Also called the pyramid, up-and-down or the seesaw system. A progressive betting system where the goal is to win one unit. On losses betting progresses as follows: 1 2 3 4 5 6 7 8 9... On wins betting is lowered by one unit until your bankroll returns to zero. The Contra-D'Alembert is just the opposite where the player increases bets after each win and reduces it by one after each loss.
[79 Ainslie How to Gamble in a Casino 69]

Dalton, Michael. Author of the book The Encyclopedia of Casino Twenty-One (this book) and editor of the Blackjack Review Network.   Former publisher of Blackjack Review magazine which ceased operations in 1998.  Michael Dalton has a Bachelor of Science degree in Space Science / Physics and a Master of Science in Space Technology and is retired from the National Aeronautics and Space Administration (NASA) where he worked for over 30 years.   See Maddog. See About the Author.  You can email him directly at editor [NO SPAM] @ BJRnet . com.
[ http://www.BJRnet.com ]

DAH. An NBJ acronym for dealer average hand.

DAS. Acronym for double after split.

David. (c1971) (Keith Taft) A concealable blackjack computer developed by Keith Taft. Taft designed his first such strategy computer and used it successfully in Nevada's casinos in 1971. Arnold Snyder reportedly wrote the manual for this computer. This device is a perfect-strategy computer. George and Thor were reportedly later versions of David. See Casey. See Fred.
[4/16/79 Sports Illustrated]
[1/80 Gambling Times]
[6/84 Snyder Blackjack Forum 4]
[9/84 Snyder Snyder Writes Manual for David BJF]

Davis, E. Clifton.  Developer of the New Blackjack (NBJ) method.
[ http://www.ecliftondavis.com/ ]

daub. {CHS}. As in a card-dauber. A paste or fluid (e.g., India ink or aniline pencil) used to mark the back of playing cards for the purposes of cheating. Also called rouge or smear.

DBH Count. {PCS/L?} (David Barrios) (c1986) ???

DBR. An NBJ acronym for dealer break rate.

DBS. An acronym for double after split but not typically used in this dictionary. See DAS.
[Wong Current Blackjack News]

DBX. Acronym for Double Exposure.  See DE.

DC17. Acronym for dealer's choice on whether to hit or stand on S-17.

DD. 1) Acronym for double down. 2) Acronym for double-deck.

DE. Acronym for Double Exposure.  See DBX.

dead table. A casino term referring to a table with no players.

deal. 1) As in to deal cards. The act of distributing cards to a player or players. Dealers will always deal from left to right. 2) As in the deal. The same as hand. See payoff.

dealer. The casino employee conducting the blackjack game, dealing the cards, making the payoffs and seeing that rules are followed at his or her table. All casino dealers are instructed to play their hands according to a fixed and specified set of instructions. For example, all dealers must hit a 16 and stand on hard 17, even if all players have hands of 18 or more. According to one instructor the three basic elements to a good "21" dealer are the following:

See S-17. See H-17.
[11/81 Wong Casino Rules... - Nevada BJ Vol.3,182]
[82 Gaem Keeping Notes on BJ Dealers Vol.20,26]
[85 Do Dealers Count BJF]
[6/86 Flower Interview With a Dealer BJF 31]
[91 Janik/Smith How to Deal BJ VIDEO MANUAL]
[ http://www.BJRnet.com/member/openfree_archive6/index.cgi?read=4210 ]

dealer bias. See bias.

deck. As in a deck of cards. There are 52 cards in a regulation deck of modern-day playing cards. Four suits of ace, 2, 3, 4, 5, 6, 7, 8, 9, 10, jack, queen, and king make up a full deck. Today's blackjack games typically use from 1 or 2 decks (hand-held) to 4,5,6, or 8 decks (dealt from a shoe). See pack, ten.

dependent trials. See independent trials.

depth charging. {CS} A single-deck strategy developed and coined by Arnold Snyder that allows the player to play a winning game without using a bet spread based on count information. Depth chargers use the depth of the deal as the primary method of gaining a long-run advantage. Depth chargers will always bet more deep in the deck, even when the count is negative. An advanced card counting system with an excellent playing efficiency is required.
[83 Snyder Blackbelt in Blackjack 72]

desirability index. (DI) Term coined by Donald Schlesinger in his book Blackjack Attack.  The higher the index number, the better the game.  The DI is a number based on a relationship between the win-rate and the standard deviation for a particular game.

deuce. A playing card with a value of two (2).

device. As in an electronic or mechanical device.  See cheating.

D. Howard Mitchell. (DHM) a.k.a. Edward Gordon.  Author and developer of the DHM card counting systems.

DHM Expert. {PCS/L1}. (D. Howard Mitchell a.k.a. Edward Gordon) (c1973). DHM Associates, Arroyo Grande, CA. This system requires the player to count four different groups separately (low 2-5, middle 6-9, high 10, and aces). The DHM systems were once available through the Gambling Times Systems Shop. Originally based on the Gordon Count.

A 2 3 4 5 6 7 8 9 10
0 1 1 1 1 0 0 0 0 -1

BC = .86 PE = .56

[2/78 Mitchell BJ Systems From BS to Expert GT 15]
[78 Mitchell An Overview of Blackjack C&S Vol.4, 47]
[80 Revere Playing Blackjack as a Business 172]
[80 Snyder Blackjack Forum 80]
[81 Uston Million Dollar Blackjack 326]
[3/84 Snyder DHM Expert Vs Uston APC BJF 16]

DHM Simplified. {PCS/L1}. (D. Howard Mitchell a.k.a. Edward Gordon) (c1974). A simplified version of DHM Professional. Originally based on the Gordon Count.

A 2 3 4 5 6 7 8 9 10
0 1 1 1 1 0 0 0 0 -1

BC = .86 PE = .56

DHM Professional. {PCS/L1}. (D. Howard Mitchell a.k.a. Edward Gordon) (c1974). Same as DHM Simplified but with a side count of aces.

DHM Ultimate. {PCS/L1}. (D. Howard Mitchell a.k.a. Edward Gordon) (c1978). This system is based on use of an on-line computer that is notified of every card as it is drawn. According to Mitchell, this system was inspired by the Sklansky Key Card Concept.
[84 Gwynn How Good Can a Pocket BJ Computer Be?]
[84 DHM Ultimate System Computer Simulations BJF]

One advantage of the 2,3,4,5 low count is the effectiveness against the Over/Under 13 side bet now available in some casinos.

. Acronym for desirability index.

DiBenedetto, Ron. Developer of the Precision Blackjack method.

D1.gif (1275 bytes)

diamond. The red figure diamond.gif (942 bytes) marking one of the four suits of playing cards. See suit.

disadvantage. See advantage.

discard holder. See discard tray.

discard tray. Also called discard holder. The plastic or metal holder used to hold the discards until the next shuffle - usually placed to the right of the dealer. The discard tray can tell the observant player how many cards have been dealt. Card counters keep a eye on this tray to determine the conversion factor required to evaluate the true count.

discards. The cards already played. See discard tray.

discipline. Control of one's actions. Many blackjack authorities will probably tell you that self discipline is 50% (if not 75% or 95%) of the game.
[Spr 93 Dalton Lesson 4: Discipline 10]

All the winning methods in the world are useless unless the player has the discipline to execute them accurately.

DOA. Acronym for "double down on any first two cards."  See DA. See D2.

dollar.   Slang for $100.

double.   See double down

double after split. (DAS, DBS, DS). The advantageous rule that allows the player to double down after he has split a pair. PA = +.14%

double-deck. A blackjack game played with two decks and typically hand dealt. PA = -.33%

11 is a great double down hand!11 is a great double down hand!double down. (D, DD). The option that allows the player to double the value of his bet after looking at his first two cards. If a player doubles his bet he will receive only one additional card. Only a few casinos allow the player to double his bet after receiving more than two cards. Doubling down properly gives the player a 1.6% gain over a mimic the dealer strategy. The following figures are the basic strategy player's approximate losses if doubling is forbidden.

If doubling is permitted on 3 or more cards the player has a gain of approximately 0.2%.

double down flash. (DDF) A term coined by Steve Forte to refer to a tell when the dealer intentionally flashes a face down double down card to a player.
[86 Forte Read the Dealer 17]

double down rescue. (DDR) A Spanish 21 rule term.  After doubling, if you are dissatisified with your non-busted hand,  you may surrender.

Double Edge Blackjack. (DE) This game variation allows players to play two hands with a single wager.
[10/30/92 Double Edge at Edgewater, Laughlin CP]

Double Exposure. (DBX, DX, DE) Also called zweikartenspiel. Also called See-Thru 21. A game variation first introduced at Bob Stupak's Vegas World (October 1979) in Las Vegas in which the dealer's hole-card is exposed. A number of other casinos in Las Vegas and Northern Nevada also offer this game but usually only at one or two tables. Typical rules include:

In these types of games you can generally be assured that some rules have been changed to restore to the house its overall edge. On the other hand, if you can find double exposure games with regular blackjack rules they are worth playing. See front loading.
[80 Braun How to Play Winning Blackjack 161]
[81 Uston Million Dollar Blackjack 40]
[81 Wong Professional Blackjack 128]
[81 Wong Nevada Blackjack Vol.3,75]
[90 Wong Instant Update]
[90 Zender Card Counting for the Casino Exec. 135]

Double Play 21. A blackjack variation that allows the player to bet on two betting spots instead of one. The game is dealt as usual except the dealer shows two up-cards which are played out against each player's hand respectively. First offered at the Tropicana Casino in Las Vegas in 1992.

double up. To increase a bet by the same amount. See press.

doubling for less. To place an additional bet which is less than one's original wager and to receive only one more card. This is usually not recommended in situations where doubling is advisable, however, money management concerns may dictate otherwise. If their bankroll is in jeopardy, players are usually recommended to consider hitting or standing before doubling for less. See double down.

Downtown. Usually a reference to downtown Las Vegas. This is the area where many Las Vegas dealers started their dealing career. It has often been classified as an area of low prestige and low tokes.
[80 Solkey Dummy Up and Deal 112]

Downtown rules. Typical Downtown rules in Las Vegas, NV differ from Las Vegas Strip rules as follows:

Dealer hits soft 17.

[12/90 Wong Instant Update CBN]

Dracman, Frank. See Fred.

draw. As in to draw a card. See hit.

drinking. The drinking of alcoholic beverages is allowed in most casinos and usually encouraged for obvious reasons. Most casinos even offer free drinks to their customers. Don't expect to play a winning game of blackjack and drink at the same time.  Pretending to drink at the table is a common camouflage technique for card counters.

drop. A casino management term for the total amount of money in cash or markers that players have used for the purchase of chips at a casino table. See drop box. See hold.

drop box. A box, locked to the underside of a blackjack table, into which the dealer deposits all currency.

drop cut. The dealing technique of holding a stack of chips in one hand and touching them to the table. The dealer then lifts some of them, leaving a small stack of the precise number of chips wanted.
[80 Solkey Dummy Up and Deal 112]

DS. Acronym for double after split.

DSA. Acronym for double after split aces.  See DACE.

Dubner Hi-Low. {PCS/L1}. (Harvey Dubner) (c1963). See Hi-Lo.

dummy up. As in dummy up and deal. An oral command given by a pit boss to a dealer, telling the dealer to stop chatting with the players.
[80 Solkey Dummy Up and Deal]

dump. To lose a large amount of money quickly. See dumping table.

dumping table. A casino term referring to a table where the players have been winning excessively.

Du-Rite at 21 Strategy Wheel. {BS}. (Leon Dubey) (c1967, 1980) Du-Rite Co, West Babylon, Long Island, NY. A basic strategy wheel.
[80 Dubey No Need to Count 203]

DX. Acronym for Double Exposure.   See DE.  See DBX.

Dylag Card Counting Prevention Apparatus. See blackjack shields.

Last Update 09/12/10