Definition of all-play-all in US English:

all-play-all

adjective

Chess
  • Of, relating to, or designating a chess tournament in which each of the players plays each of the others in turn.

noun

Chess
  • An all-play-all tournament.

Origin

1950s; earliest use found in British Chess Magazine. From all [noun] + play + all [noun].

Pronunciation

all-play-all

/ˌɔːl pleɪ ˈɔːl/