The word overall is also an adjective meaning "above everything".

Overalls are usually used as protective clothing when working, but they have sometimes been items of fashion.
There are two sorts of garment called an overall.

Bib-and-brace

These are trousers with an attached front patch covering the chest and with attached braces (U.S. suspenders) which go over the shoulders. Some people use the word "overall" for this garment only and not for a boilersuit.

Bib overalls are generally made of blue denim, and often have riveted pockets, similar to those of blue jeans. Bib overalls have long been associated with rural men in the U.S. South and Midwest, especially farmers. They are often worn with long_johns or a red union suit underneath, or with a t-shirt or no shirt at all in warmer weather. Since the 1960s, different colors and patterns of bib overalls have been increasingly worn by young people of both sexes, often with one of the straps worn loose or unfastened along the side and under the arm.

Boilersuit

This is sometimes called a coverall. It is a one-piece garment with full-length sleeves and legs like a jumpsuit, but usually less tight-fitting and used as protective clothing at work. One main feature is that it has no gap between jacket and trousers and no loose jacket tails. It usually has a front fastening extending from above the waist to the neck, or the whole length of the front of the body, with no lapels. This fastening can be:-

buttoned.

a zipper.

velcro, as nowadays in the British Royal Air Force (RAF).

popper buttons or press-studs.

They are often issued by factories to their workmen, with the firm's badge on it.
The French police unit called CRS use boilersuits as uniforms.
A dark blue coverall is the current working uniform of the U.S. Navy, with the owner's name and "U.S. Navy" on the chest, and rank insignia on the collar points.

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