to take a long deep audible breath, e.g. in relief, weariness, or grief

said esp of the wind: to make a sound like sighing

(+ for) to grieve or yearn

He's still sighing for the days of his youth

to express (something) by or with sighs

an act of sighing, esp when expressing an emotion or feeling, e.g. weariness or relief

a sound of or resembling sighing

sighs of the summer breeze