Sigh

A sigh is a kind of paralinguistic respiration in the form of a deep and especially audible, single exhalation of air out of the mouth or nose, that humans use to communicate emotion. It is voiced pharyngeal fricative, sometimes associated with a guttural glottal breath exuded in a low tone. It often arises from a negative emotion, such as dismay, dissatisfaction, boredom, or futility. A sigh can also arise from positive emotions such as relief, particularly in response to some negative situation ending or being avoided. Like a gasp, a yawn, or a moan, a sigh is often an automatic and unintentional act. In literature, a sigh is often used to signify that the person producing it is lovelorn.

Scientific studies show that babies sigh after 50 to 100 breaths. This serves to improve the mechanical properties of lung tissue, and it also helps babies to develop a regular breathing rhythm. Behaviors equivalent to sighing have also been observed in animals such as dogs, monkeys, and horses.

In text messages and internet chat rooms, or in comic books, a sigh is usually represented with the word itself, 'sigh', possibly within asterisks, *sigh*.