What does "concentrate" mean?

Concentrate: To increase the strength and diminish the bulk of, as of a liquid or an ore; to intensify, by getting rid of useless material; to condense; as, to concentrate acid by evaporation; to concentrate by washing; -- opposed to Ant: dilute. Spirit of vinegar concentrated and reduced to its greatest strength. Arbuthnot.

Additional senses

  1. 2.To approach or meet in a common center; to consolidate; as, population tends to concentrate in cities.

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