exhalar

Exhalar is a verb meaning to exhale or to emit air, vapor, or scent from the lungs or from a source. In Spanish and Portuguese, exhalar is used primarily to describe the act of breathing out, though it can also refer to releasing vapors or odors from other objects. In English, the equivalent term is exhale.

Etymology: The word derives from Latin exhalāre, combining ex- “out” with halāre “to breathe.” Through Romance languages, exhalar has retained the sense of emitting breath or vapor, and it is used in both technical and literary contexts.

Physiology: Exhalation is the phase of breathing during which air exits the lungs. In quiet breathing, exhalation is largely passive and results from the relaxation of the diaphragmatic and intercostal muscles together with the elastic recoil of the lungs and chest wall. During exercise or certain clinical conditions, expiratory muscles such as the internal intercostals and abdominal muscles contract to force air out more rapidly and completely, aiding ventilation and gas exchange.

Clinical and practical notes: In medicine, exhalation is assessed through spirometry to gauge lung function, with measures such as forced expiratory volume (FEV1) and vital capacity. Exhaled breath analysis can detect gases and volatile compounds, including nitric oxide as a marker of airway inflammation. Exhalation also appears in everyday language or literature to describe the release of vapors, scents, or other substances from a source.

See also: respiration, breathing, expiration.