Antagonize (verb)

1. To provoke or incite hostility or opposition in.
2. To act in opposition to or compete against.
3. To cause a muscle to contract in opposition to another muscle, especially the agonist muscle.
4. To interfere with or block the action of another, especially a neurotransmitter or hormone.

Origin:

From the greek ἀνταγωνιστής (antagonistes), meaning "opponent" or "adversary".

Examples:

1. The new policy antagonized the employees and they went on strike.
2. The new law antagonized the business community and they protested.
3. His behavior antagonized the other players and they refused to play with him.
4. The antagonist muscle antagonizes the agonist muscle in this exercise.
5. The antagonist drug antagonizes the action of the neurotransmitter in the brain.