A release of stress through breathing motions. / (idiomatic) A reassurance or support, something that reduces stress from an arduous activity.

plural of sigh of relief

(informal, humorous) A sigh of longing or disappointment.

A vocal sound of gradually descending pitch, between a yawn and a sigh, sometimes used in speech therapy.

plural of yawn-sigh

(idiomatic) to be relieved; to feel relief.