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c.1600, "action of competing," from Latin competitionem (nominative competitio) "agreement, rivalry," noun of action from past participle stem of competere (see compete). Meaning "a contest for something" is from 1610s. Sense of "rivalry in the marketplace" attested from 1793; that of "entity or entities with which one competes" is from 1961, especially in business.
competition com·pe·ti·tion (kŏm'pĭ-tĭsh'ən)
The process by which the activity or presence of one substance interferes with or suppresses the activity of another substance with similar affinities, as of antigens.
The simultaneous demand by two or more organisms for limited environmental resources.
in ecology, utilization of the same resources by organisms of the same or of different species living together in a community, when the resources are not sufficient to fill the needs of all the organisms