0 a short coat made of denim (= a thick, strong cotton cloth, often blue, used especially for making jeans): --
He's taken to dressing in young people's clothes. He wears denim jackets - with the collar up! - and sunglasses.
I tended to dress drably in black trousers, dark grey pullover and black denim jacket.
A denim jacket will work with everything from your evening dress to skirts, trousers or even your sarong.
The black and red badge Marty wears on his denim jacket says "Art in Revolution".