reaction

Something you do, say, or feel because something else has happened.

• His first reaction was to laugh.
• What was your reaction to the invitation?
• Their reactions showed how surprised they were.

How to use it: reaction to something (Her reaction to the news surprised me.)

Similar words: response

Common phrases: first reaction, immediate reaction, reaction to something, public reaction

A change in which substances join together or break apart to form different substances.

• The reaction produced a gas.
• Heat can speed up some reactions.
• We observed a reaction between the acid and the metal.

How to use it: reaction between A and B (The reaction between the two chemicals produces heat.)

Similar words: chemical reaction

Common phrases: chemical reaction, reaction with oxygen, reaction between substances