reaction noun - Definition, pictures, pronunciation and usage …
https://www.oxfordlearnersdictionaries.com/definition/english/reaction
WEB[countable, uncountable] a response by the body, usually a bad one, to a drug, chemical substance, etc. If you have a bad reaction, discontinue use immediately. reaction to something to have an allergic reaction to a drug. Adverse reactions to certain foods can take a few days to manifest. Extra Examples. Topics Health problems b1.
DA: 72 PA: 26 MOZ Rank: 48