The word 吸气 is formed by combining the character 吸, meaning "to inhale" or "to suck", which incorporates the mouth radical 口 to indicate the action involves the mouth, along with the phonetic component 及, and the character 气, meaning "air" or "breath", originating from a pictographic symbol for vapor. In this compound, 吸 specifies the action of drawing in, and 气 specifies what is drawn in, resulting in the meaning "to inhale air".