Additionally, it may refer to:

• Antagonism (chemistry), where the involvement of multiple agents reduce their overall effect
• Antagonism (philosophy), a principle, force or factor that is an active resistance, opposition, or contentiousness
• Antagonism (pharmacology), when a substance binds to the same site an agonist would bind to without causing activation of the receptor
• Antagonism (phytopathology), the action of any microbes that suppresses the activity of a plant pathogen.

See also

• Antagonist (disambiguation)