The most common and most likely answer to this crossword clue is the 6 letter word DEUCES
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The straight part
We know that "low cards" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case low cards = deuces.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does DEUCES mean?
DEUCES noun- A card with two pips, one of four in a standard deck of playing cards.
- A side of a die with two spots.
- A cast of dice totalling two.
- The number two.
- A tied game where either player can win by scoring two consecutive points.
- A curveball.
- A '32 Ford.
- (in the plural) 2-barrel (twin choke) carburetors (in the phrase 3 deuces: an arrangement on a common intake manifold).
- (restaurants) A table seating two diners.
- A piece of excrement.
- (epithet) The Devil, used in exclamations of confusion or anger.
- A pair of twos.
- Peace; goodbye (because of the associated gesture holding up two fingers)