QUOTE : What is a sigh? That would be another good subject for a field study. Is it just a long, deep, audible exhalation of breath? Rose's sigh was intense but not subdued. It was frustrated but not yet sad. A sigh resets the respiratory system so it was possible that my mother had been holding her breath, which suggests she was more nervous than she appeared to be. A sigh is an emotional response to being set a difficult task.