They spread outward in every direction to regions where they are in low concentration. Your nose is able to detect the smell of the cologne or perfume even if you are quite a distance from the bottle that has been opened. Diffusion occurs in all states of matter: solid, liquid, and gas.
enclave, exclave - An enclave is a group or area different from the surroundings, a secured area within another secured area, from Latin clavis, key; an exclave is the same thing, but usually describes a portion of a country separated from the main part and surrounded by politically alien territory.
5 Shapes of Countries and Enclaves and Exclaves. Definition - The boundaries of a country and the shape of the land that it encompasses can present problems or it can help unify the nation. Each shape of state has advantages, as well as disadvantages.