How to Say "reaction" in Spanish
The Spanish word for “reaction” is “reacción” — A2 level. This is a very common word in everyday Spanish.

Examples
Su primera reacción al ver el regalo fue sonreír.
Her first reaction upon seeing the gift was to smile.
La reacción del mercado ante la nueva ley fue inmediata.
The market's reaction to the new law was immediate.
Tuvimos una fuerte reacción alérgica al polen.
We had a strong allergic reaction to the pollen.
Gender Alert
Remember that 'reacción' is always feminine, so you must use 'la' before it, or feminine adjectives: 'una reacción fuerte' (a strong reaction).
Noun vs. Verb
Mistake: “Using 'reacción' when you mean the verb 'to react' (reaccionar).”
Correction: Use 'reacción' (the noun) to describe the result, and 'reaccionar' (the verb) to describe the action: 'Él reaccionó bien' (He reacted well).
Other Meanings of “reacción”
“reacción” can also mean:
- Chemical or physical process(B2, formal)
Related Translations
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