Meanings of unbuttoned vest in English

The buttonless shirt bulged in stiff waves beneath his unbuttoned vest.

Upon his unbuttoned vest was the shield of the United States Forest Service.

He wore his usual work uniform of plaid flannel shirt and unbuttoned vest.

His sleeves were rolled over his fat forearms, and the two flaps of his unbuttoned vest dangled as he bent to bail out the boat.

And the new-comer, catching his reins between his knees, took papers and tobacco from the pocket of a sagging, unbuttoned vest and made a cigarette.