radius Meaning & Definition
What Does Radius Mean?
Radius is used as a noun meaning a line segment extending from the center of a circle or sphere to the circumference or bounding surface. It is also used to mean the bone on the thumb side of the human forearm.
Radius at a Glance
| Part of speech | noun |
|---|---|
| Pronunciation | /ˈrā-dē-əs/ |
| Syllables | 3 |
| Synonyms | spoke and r |
| Plural | radii |
| First known use | 1578 |
Radius Definition (Noun)
- a line segment extending from the center of a circle or sphere to the circumference or bounding surface
- the bone on the thumb side of the human forearm
- a corresponding part of vertebrates above fishes
- the third and usually largest vein of an insect's wing
- the length of a radius
a truck with a short turning radius
- the circular area defined by a stated radius
- a bounded or circumscribed area
- a radial part
- the distance from a center line or point to an axis of rotation
Synonyms of Radius
Radius synonyms and antonyms →Radius in a Sentence
Fatima claims to have visited all the bars within a five-mile radius of her Manhattan apartment.
a truck with a short turning radius
Word Forms & Grammar
ra·dii
ra·di·us·es
radii
radius
radiuses
radius (plural radii or radiuses)
radius (third-person singular simple present radiuses, present participle radiusing, simple past and past participle radiused)
Words That Rhyme With Radius
Origin of Radius
Origin 1: Latin, ray, radius
Origin 2: Borrowed from Latin radius (“ray”). Doublet of ray.
First Known Use
1578
Pronouncing Radius
The standard pronunciation of radius is /ˈrā-dē-əs/, spoken in 3 syllables, with the main stress on the first syllable (rā).
Common Questions About Radius
What part of speech is radius?
Radius is a noun.
What is another word for radius?
Close synonyms of radius are spoke and r. See the full list of radius synonyms and antonyms.
What is the plural of radius?
The plural of radius is radii.