The word "憋气" is formed by combining the character "憋", which means to suppress or hold back and is itself composed of the radical "心" (heart) indicating a relation to inner states and the component "敝" contributing to its sound and sense of constriction, with the character "气", meaning breath or air. This creates a compound where "憋" modifies "气" to literally express "holding back breath", referring directly to the act of breath-holding or the feeling of being stifled.