Properly conducted conditions for a game, giving all participants an equal chance. Also used more widely to mean fairness and justice in contexts other than games.
Shakespeare coined this phrase and used it in several of his plays; for example, The Tempest, 1610:
Yes, for a score of kingdoms you should wrangle,
And I would call it, fair play.
The term migrated into 'fair dinkum', which is well-known as an Australian phrase but may have travelled there from England. An unambigously Australian term meaning the same thing as 'fair play' is the more recent 'fair go'. This is first recorded in the Australian author Lewis Stone's book Jonah, 1911:
"Get set!--get set!" cried the boxer, lolling in his seat with a nonchalant air; and in a twinkling a bright heap of silver lay in front of each player, the wagers made with the gaffers opposite. The spinner handed his stake of five shillings to the boxer, who cried "Fair go!"
See also - foul play.
See other - phrases and sayings from Shakespeare.