the world > textiles and clothing > clothing > types or styles of clothing > clothing for body or trunk (and limbs) > [noun] > that covers or protects other clothing > overall (7)
Chiefly British. A protective outer garment; (now esp.) a loose coat or smock worn to keep the clothes beneath clean.
Chiefly English regional (Cornwall). A pinafore; an overall. Now rare.
slang. A pair of overalls; a similar garment such as a boiler suit or flying suit.