Definition: A "birdcage mask" is a type of protective gear that a catcher (the player who stands behind home plate in baseball or softball) wears. It has a strong wire frame that covers the face, just like a cage, to protect the catcher from being hit by the ball.
In more advanced discussions, you might talk about the design or technology of the birdcage mask, or compare it to other types of masks used in sports.
While "birdcage mask" does not have specific idioms or phrasal verbs associated with it, you might come across phrases like:
In summary, a "birdcage mask" is an important piece of equipment in baseball and softball that protects the catcher’s face. It combines safety with the need for visibility and mobility during the game.