RADIUS (radii)

Pronunciation (US):

(GB):

IPA (US):

Irregular inflected form: radii   

 Dictionary entry overview: What does radius mean? 

• RADIUS (noun)
  The noun RADIUS has 5 senses:

1. the length of a line segment between the center and circumference of a circle or sphere

2. a straight line from the center to the perimeter of a circle (or from the center to the surface of a sphere)

3. a circular region whose area is indicated by the length of its radius

4. the outer and slightly shorter of the two bones of the human forearm

5. support consisting of a radial member of a wheel joining the hub to the rim

  Familiarity information: RADIUS used as a noun is common.

 Dictionary entry details 

• RADIUS (noun)

Sense 1

Meaning:

The length of a line segment between the center and circumference of a circle or sphere

Classified under:

Nouns denoting attributes of people and objects

Synonyms:

r; radius

Hypernyms ("radius" is a kind of...):

length (the linear extent in space from one end to the other; the longest dimension of something that is fixed in place)

Hyponyms (each of the following is a kind of "radius"):

semidiameter (the apparent radius of a celestial body when viewed as a disc from the earth)

radius of curvature (the radius of the circle of curvature; the absolute value of the reciprocal of the curvature of a curve at a given point)

Holonyms ("radius" is a part of...):

diam; diameter (the length of a straight line passing through the center of a circle and connecting two points on the circumference)

Sense 2

Meaning:

A straight line from the center to the perimeter of a circle (or from the center to the surface of a sphere)

Classified under:

Nouns denoting two and three dimensional shapes

Hypernyms ("radius" is a kind of...):

straight line (a line traced by a point traveling in a constant direction; a line of zero curvature)

Derivation:

radial (relating to or moving along or having the direction of a radius)

Sense 3

Meaning:

A circular region whose area is indicated by the length of its radius

Classified under:

Nouns denoting spatial position

Context example:

they located it within a radius of 2 miles

Hypernyms ("radius" is a kind of...):

part; region (the extended spatial location of something)

Sense 4

Meaning:

The outer and slightly shorter of the two bones of the human forearm

Classified under:

Nouns denoting body parts

Hypernyms ("radius" is a kind of...):

arm bone (a bone in the arm)

Holonyms ("radius" is a part of...):

forearm (the part of the superior limb between the elbow and the wrist)

Derivation:

radial (relating to or near the radius)

Sense 5

Meaning:

Support consisting of a radial member of a wheel joining the hub to the rim

Classified under:

Nouns denoting man-made objects

Synonyms:

radius; spoke; wheel spoke

Hypernyms ("radius" is a kind of...):

support (any device that bears the weight of another thing)

Holonyms ("radius" is a part of...):

bicycle wheel (the wheel of a bicycle)

cartwheel (a wheel that has wooden spokes and a metal rim)

wagon wheel (a wheel of a wagon)

 Context examples 

Its mean radius is about 80 percent the size of the largest planet in the Solar System, Jupiter, but despite its small size it is very dense.

(Astronomers discover smallest known star, Wikinews)

A 100-solar-mass star, as a black hole, would have a radius of about 180 miles (290 kilometers).

(Elusive Middleweight Black Hole Found at Center of Giant Star Cluster, The Titi Tudorancea Bulletin)

Discovered in 2018 by NASA's Transiting Exoplanet Satellite Survey (TESS) mission, planet LHS 3844b is located 48.6 light-years from Earth and has a radius 1.3 times that of Earth.

(A Rare Look at a Rocky Exoplanet's Surface, NASA)

The planet has a mass and radius nearly identical to that of Jupiter, making it the largest transiting circumbinary planet ever found.

(New Planet Is Largest Discovered That Orbits Two Suns, The Titi Tudorancea Bulletin)

WASP-127b has a radius 1.4 times larger than Jupiter but has only 20% of its mass.

(Multiple metals – and possible signs of water – found in unique exoplanet, University of Cambridge)

“That circle is drawn at a radius of ten miles from the village. The place we want must be somewhere near that line. You said ten miles, I think, sir.”

(The Adventures of Sherlock Holmes, by Sir Arthur Conan Doyle)

That gives a radius of ten or twelve miles, and he does it once, or sometimes twice, a day.

(The Return of Sherlock Holmes, by Sir Arthur Conan Doyle)

A skeletal muscle of the forearm originating from the posterior surfaces of the ulna and radius and the interosseous membrane.

(Abductor Pollicis Longus, NCI Thesaurus)

Based on the observations, NGTS-1's radius is 0.573±0.077 R☉ (solar radius) and using that value, astronomers calculated its weight to be about 0.598 M☉ (solar mass).

(Astronomers report dwarf star with unexpectedly giant planet, Wikinews)

It results from the formation of a fibrotic band which constricts the full radius of the digit and eventually causes the spontaneous autoamputation.

(Ainhum, NCI Thesaurus)