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definitions

inside straight

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noun

Poker. a set of four cards, as the five, seven, eight, and nine, requiring one card of a denomination next above or below the second or third ranking cards of the set to make a straight.

Idioms

    draw to an inside straight, to build up hopes for something that has little or no chance of happening.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019