The air inhaled and exhaled in respiration. The act or process of breathing; respiration. The capacity to breathe, especially in a natural and unlabored manner: shortness of breath. Spirit or vitality; life. A single respiration: a deep breath. Exhaled air, as evidenced by vapor, odor, or heat. A momentary pause or rest. A momentary stirring of air. A slight gust of fragrant air. A trace or suggestion: a breath of scandal. A softly spoken sound; a whisper. Linguistics Exhalation of air without vibration of the vocal cords, as in the articulation of p and s. one At or almost at the same time. out of breath Breathing with difficulty, as from exertion; gasping. under (one's) breath In a muted voice or whisper.