How to Say "radioactive" in Spanish
The Spanish word for “radioactive” is “radiactivo” — B2 level.
Examples
El uranio es un elemento muy radiactivo.
Uranium is a very radioactive element.
Debemos tener cuidado con los residuos radiactivos.
We must be careful with radioactive waste.
La zona fue evacuada por una fuga radiactiva.
The area was evacuated due to a radioactive leak.
Matching the Noun
This word changes its ending to match what you are describing. Use 'radiactivo' for masculine words (el material) and 'radiactiva' for feminine words (la sustancia).
Word Placement
In Spanish, technical adjectives like this almost always come AFTER the noun they describe. Say 'material radiactivo', not 'radiactivo material'.
The 'O' vs 'A' spelling
Mistake: “Muchos estudiantes escriben 'radioactivo' con O.”
Correction: While 'radioactivo' is common and accepted, 'radiactivo' (with an A) is the version preferred by official Spanish language experts (RAE).
Related Translations
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