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Definition of activation energy
: the minimum amount of energy required to convert a normal stable molecule into a reactive molecule
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activation energy
nounac·ti·va·tion energy | \ ˌak-tə-ˈvā-shən- 
\
\Medical Definition of activation energy
: the minimum amount of energy required to convert a normal stable molecule into a reactive molecule
— called also energy of activation
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Time Traveler for activation energy
The first known use of activation energy was in 1924
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