Brozel

Brozel is a contract bridge bidding convention used to intervene after an opposing one notrump opening bid. It features the following calls:

Double - shows any single suit; advancer bids 2, after which intervenor corrects to his actual suit. This was originally played as requiring either a solid suit or a very good suit and an entry, leaving advancer the opportunity to pass with a couple of side-suit stoppers, though many partnerships now allow a weaker suit.
2 - shows clubs and hearts
2 - shows diamonds and hearts
2 - shows hearts and spades
2 - shows spades and an unspecified minor suit
2NT - shows clubs and diamonds

Brozel is named loosely after its creator, Bernard Zeller.