Biography Wikipedia
Wikipedia:
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.
Andy Murray letting out a sigh during a game.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*.
