concentrate >> /ˈkɑnsənˌtreɪt/
Definition: [verb] Focus one's attention or mental effort on a particular object or activity.
Example: she couldn't concentrate on the movie
Definition: [verb] Gather (people or things) together in numbers or in a mass.
Example: wealth was concentrated in the hands of the governing elite
Definition: [verb] Increase the strength or proportion of (a substance or solution) by removing or reducing the water or any other diluting agent or by selective accumulation of atoms or molecules.
Example: plants and microorganisms can concentrate metals from the environment
Definition: [noun] A substance made by removing water or other diluting agent; a concentrated form of something, especially food.
Example: apple juice concentrate