What is the meaning of Sigh?

To inhale a larger quantity of air than usual, and immediately expel it; to make a deep single audible respiration, especially as the result or involuntary expression of fatigue, exhaustion, grief, sorrow, frustration, or the like.

To lament; to grieve.

To utter sighs over; to lament or mourn over.

To make a sound like sighing.

To exhale (the breath) in sighs.

To express by sighs; to utter in or with sighs.

A deep, prolonged audible inhale and exhale of breath; as when fatigued, frustrated, grieved, or relieved; the act of sighing.

a manifestation of grief; a lament.

A person who is bored.

An expression of fatigue, exhaustion, grief, sorrow, frustration, or the like, often used in casual written contexts.

Source: wiktionary.org