nocivo

harmful

adjective noh-SEE-boh Rare

Origin: Latin nocivus, from nocere (to harm)

Also means

noxious

Usage Note

Nocivo describes substances, habits, or influences that cause harm — common in health and environmental contexts: gases nocivos (noxious gases), hábitos nocivos (harmful habits). It is more formal and written than dañino (the everyday synonym) and often collocates with para la salud (for health). The noun form is nocividad.

Examples

"El tabaco es nocivo para la salud."

Natural Translation

Tobacco is harmful to health.

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