Reaction
/riˈækʃən/noun
A response to a stimulus, event, or action.
Did you know?The word comes from Latin roots meaning “to act back,” while its scientific sense developed as chemists began describing substances responding to one another.
Etymological Timeline
Proto-Indo-European
PIE
*h₂eǵ-
“To drive, lead, or set in motion”
Classical Latin
Latin
agere
“To do, drive, lead, or carry out”
Late Latin
Latin
reagere
“To act back or drive back”
Medieval Latin
Latin
reactio
“A reacting or action in return”
15th–16th Century
French
réaction
“A return action or response”
Early 17th Century
English
reaction
“Action in response or opposition”
Modern English
English
reaction
“A response to a stimulus, event, or action”