How to Say "radius" in Spanish
The Spanish word for “radius” is “radio” — B1 level.
English → SpanishB1
NounB1
Geometry; the distance from the center to the edge of a circle

Examples
El radio de la Tierra es de aproximadamente 6,371 kilómetros.
The Earth's radius is approximately 6,371 kilometers.
Necesitamos un círculo con un radio de cinco centímetros.
We need a circle with a radius of five centimeters.
La antena wifi tiene un radio de alcance de 20 metros.
The Wi-Fi antenna has a range of 20 meters.
The Masculine Version
When 'radio' means radius, spoke, or range, it's a boy! So you use 'el radio' or 'un radio'. This is the complete opposite of the broadcast meaning.
Mixing up the Genders
Mistake: “Calcula *la radio* del círculo.”
Correction: Calcula *el radio* del círculo. For math and science topics, think masculine ('el').
Other Meanings of “radio”
“radio” can also mean:
- The bone in the forearm(B2, formal)
Related Translations
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