Definition of all fives in English:

all fives

Pronunciation /ˌɔːl ˈfʌɪvz/

noun

  • 1 humorous "on all fives": on hands, knees (or feet), and another part of the body (later especially the buttocks). Compare "on (also upon) all fours".

    In later use chiefly in the contexts of hiking, climbing, etc.

  • 2Cards
    A variation of all fours in which the winner of a trick scores the face value of any trump cards it contains, as well as an additional five points if the trick contains the five of trumps.

    The winner of the game is the first player to score sixty-one points.

  • 3Games
    A game in which points are scored only when the sum of the spots at the two ends is five or a multiple thereof.

Origin

Late 18th century; earliest use found in The Monthly Review. From all + the plural of five, after all fours.