all fours

noun
1.
all four limbs or extremities; the four legs or feet of an animal or both arms and both legs or both hands and both feet of a person:
The cat rolled off the ledge but landed on all fours.
2.
(used with a singular verb). Also called high-low-jack, old sledge, pitch, seven-up. Cards. a game for two or three players or two partnerships in which a 52-card pack is used, the object being to win special scoring values for the highest trump, the lowest trump, the jack, the ace, the ten, and the face cards.
Idioms
3.
on all fours,
  1. in conformity with; corresponding exactly with.
  2. (of a person) on the hands and feet, or the hands and knees:
    I had to go on all fours to squeeze through the low opening.
Origin
1555-65
British Dictionary definitions for on all fours

all fours

noun
1.
both the arms and legs of a person or all the legs of a quadruped (esp in the phrase on all fours)
2.
another name for seven-up
Idioms and Phrases with on all fours

on all fours

On one's hands and knees, as in Seven of us were on all fours, looking for the lost earring in the sand. In this idiom fours refers to the four limbs. [ 1300s ]
Encyclopedia Article for on all fours

all fours

ancestor of a family of card games dating back to 17th-century England and first mentioned in The Complete Gamester of Charles Cotton in 1674. The face card formerly known as the knave owes its modern name of jack to this game. Originally, all fours was regarded as a lower-class game-it was much played by African Americans on slave plantations-but in the 19th century it broadened its social horizons and gave rise to more-elaborate games such as cinch, pitch, smear, and don, which include partnership play, bidding, or additional scoring cards

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