a bad reaction to the medicine.
every action has an equal and opposite reaction.
he was pleased by the audience's reaction to his performance.
his reaction to the news was to start planning what to do.
his responses have slowed with age.
his style of painting was a reaction against cubism.
John feared his mother's reaction when she saw the broken lamp.
the forces of reaction carried the election.
there was a chemical reaction of the lime with the ground water.