|1.||[ noun ] a response that reveals a person's feelings or attitude|
"he was pleased by the audience's reaction to his performance" "John feared his mother's reaction when she saw the broken lamp"
|Related terms:||response react|
|2.||[ noun ] (biology) a bodily process occurring due to the effect of some foregoing stimulus or agent|
"a bad reaction to the medicine" "his responses have slowed with age"
|Related terms:||bodily_process reflex passage learned_reaction rebound tropism immune_response automatism taxis transfusion_reaction electrical_skin_response answer kinesis overreaction double_take react|
|3.||[ noun ] an idea evoked by some experience|
"his reaction to the news was to start planning what to do"
|4.||[ noun ] (chemistry) a process in which one or more substances are changed into others|
"there was a chemical reaction of the lime with the ground water"
|Related terms:||chemical_process oxidation neutralisation reduction decomposition chemical_equilibrium chain_reaction photochemical_reaction endothermic_reaction elimination_reaction displacement double_decomposition exothermic_reaction oxidation-reduction saponification aldol_reaction addition_reaction hydrolysis chemistry|
|5.||[ noun ] doing something in opposition to another way of doing it that you don't like|
"his style of painting was a reaction against cubism"
|Related terms:||resistance backlash|
|6.||[ noun ] (politics) extreme conservatism in political or social matters|
"the forces of reaction carried the election"
|7.||[ noun ] (mechanics) the equal and opposite force that is produced when any force is applied to a body|
"every action has an equal and opposite reaction"
|Related terms:||force mechanics|