Wikipedia
Stayman convention
Stayman is a bidding convention in the card game contract bridge. It is used by a partnership to find a 4-4 or 5-3 trump fit in a suit after making a one (1NT) opening bid and it has been adapted for use after a 2NT opening, a 1NT overcall, and many other natural notrump bids.
The convention is named for Sam Stayman, who wrote the first published description in 1945, but its inventors were two other players: the British expert Jack Marx in 1939, who published it only in 1946, and Stayman's regular partner George Rapée in 1944.