small size, usually too small to see with the naked eye can be light or dark in color usually round or oval in shape can move or remain still can be composed of different materials, such as dust, dirt, or smoke
particle which has small size, usually too small to see with the naked eye particle which can be light or dark in color particle which has usually round or oval in shape particle which can move or remain still particle which can be composed of different materials, such as dust, dirt, or smoke