re
ac
tion
Plural
reactions
1
an action, thought, or feeling in response to something that has happened
- Her immediate reaction to the news was one of disbelief.
- The team's victory elicited a joyful reaction from their fans.
- His reaction to criticism was to reflect on how he could improve.
- The movie's unexpected ending provoked strong reactions from viewers.
2
(chemistry) a process in which several chemicals combine and form different substances
- The reaction between hydrogen and oxygen produces water.
- A catalyst speeds up a chemical reaction without being consumed.
- Photosynthesis is a key reaction converting CO₂ and water into glucose.
- The reaction released heat, indicating it was exothermic.
- Balancing equations ensures mass conservation in a reaction.
Synonyms:
3
an idea evoked by some experience
4
the way one's body responds to a drug, chemical substance, etc.
- The patient had an allergic reaction to the new medication.
- His skin showed a severe reaction to the chemical exposure.
- She experienced a mild reaction after receiving the vaccine.
- The doctor monitored him for any adverse reaction to the treatment.
- The rash was a reaction to the detergent used on his clothes.
Synonyms:
5
doing something in opposition to another way of doing it that you don't like
6
extreme conservatism in political or social matters
7
(mechanics) the equal and opposite force exerted by a body in response to an applied force, as described by Newton's Third Law of Motion
- When you push a wall, the reaction force from the wall pushes back equally.
- The rocket's thrust is the reaction to the expulsion of exhaust gases downward.
- The reaction of the ground propels a runner forward with each step.
- A swimmer moves forward because the water's reaction force opposes their arm strokes.
- The chair's reaction force supports your weight when you sit.