"action in resistance or response to another action or power," 1610s, from re- "again, anew" + action (q.v.). Modeled on French réaction, older Italian reattione, from Medieval Latin reactionem (nominative reactio), noun of action formed in Late Latin from past participle stem of Latin reagere "react," from re- "back" + agere "to do, act" (see act (v.)).
Originally scientific; physiological sense is attested from 1805; psychological sense first recorded 1887; general sense of "action or feeling in response" (to a statement, event, etc.) is recorded from 1914. Reaction time, "time elapsing between the action of an external stimulus and the giving of a signal in reply," attested by 1874.
例文
1. There has been a very mixed reaction to the decision.
この決定に対する反応は非常に一致していない。
2.Our instinctive reaction when someone causes us pain is to strike back.
人にかわいがられたときの本能的な反応は反撃だ。
3.Adolescent suicide is rarely an impulsive reaction to immediate distress.
青少年の自殺は、突然の不幸による衝動的な反応が少ない。
4.All new fashion starts out as a reaction against existing convention.
すべての新しいファッションは、既存の通常を破ることから始まっています。
5.Whenever recession strikes，a chain reaction is set into motion.