#breathing

• ABC (Airway, Breathing, Circulation) — A fundamental medical acronym used in cardiopulmonary resuscitation (CPR) and first aid protocols, standing for the critical steps of primary assessment and intervention: A (Airway), B (Breathing), and C (Circulation). While modern cardiac arrest guidelines often use the CAB sequence, ABC remains the cornerstone for primary trauma assessment.
• Aqualung — An autonomous underwater breathing apparatus used by divers, composed of one or more compressed air cylinders and a regulator that delivers gas at ambient pressure; a technical neologism partially adapted from the commercial trademark Aqualung. This structural device revolutionized underwater exploration, allowing complete mobility without rigid connections to the surface.
• Adenoidism — A constitutional pathological state, encountered especially in children, caused by the chronic hypertrophy of adenoid vegetations. This structural phenomenon disrupts normal development and manifests through a complex clinical picture: permanent mouth breathing, characteristic facial appearance (adenoid facies), sleep disturbances, hearing loss, and an increased predisposition to respiratory infections.
• Air-consuming — Consuming, absorbing, or utilizing large amounts of air or atmospheric oxygen to function, live, or sustain itself. In biology, the term describes organisms or processes strictly dependent on open air; in technology, it applies to internal combustion engines or turbines that require a massive air intake to create the fuel mixture.
• Breathing apparatus — As a noun, it represents a portable technical apparatus or protective device (compressed air tank with a mask) used by firefighters, divers, or miners to breathe in environments with stale air, smoke, or toxic gases. In biology (as an adjective), it describes channels, vessels, or tissues structurally adapted to transport or conduct air within an organism.
• Air-breathing jet — Utilizing the reaction of atmospheric air absorbed and expelled at high speed to produce the propulsion force necessary for movement; a system, engine, or aircraft based on burning a fuel in atmospheric oxygen. This type of structural propulsion is specific to modern turbojet airplanes, differing from rockets in that it does not carry its own oxidizer.
• Jet engine — An air-breathing jet engine (reactive) that utilizes surrounding air as an oxidizer for burning fuel and generating propulsion force through the rapid expulsion of exhaust gases. Unlike rocket engines, this structural mechanical assembly fully depends on the presence of Earth's atmosphere to function, being widely used in modern airliners and supersonic aircraft.
• Agonal — Relating to the period of terminal agony or the final moments before death; it describes the irregular, involuntary, and inefficient physiological patterns (such as agonal breathing) exhibited by an organism in structural collapse.
• Apnea — A temporary, voluntary or involuntary, cessation of breathing, characterized by the transient suspension of airflow to the lungs. This structural phenomenon can occur physiologically during diving or pathologically during sleep, leading to drops in blood oxygen levels and fragmentation of nightly rest.
• Ataxic — The feminine form of the term 'ataxic'; pertaining to ataxia or affected by this neurological disorder. As an adjective, it agrees with feminine nouns (e.g., ataxic respiration, ataxic posture); as a noun, it denotes a female patient who exhibits a lack of coordination of voluntary movements due to nerve pathway lesions.
• Atelectasis — A pathological respiratory condition consisting of the total or partial collapse of pulmonary alveoli, leading to the loss of air content from the affected lung parenchyma and the inability to perform gas exchange. It can be congenital, occurring in newborns due to failure of lung expansion at birth, or acquired in adults due to airway obstruction by mucous plugs, tumors, foreign bodies, or extrinsic compression exerted by pleural fluid or air.
• Self-relaxation — The act of relaxing oneself and its result; a psychophysical method or technique through which a person consciously and voluntarily reduces muscle tension, mental stress, and anxiety without guided therapeutic assistance. It relies on controlled breathing exercises, positive visualization, or autogenic training to induce a state of calm and inner balance.