radius

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radius

 [ra´de-us] (L.)
1. a line radiating from a center, or a circular limit defined by a fixed distance from an established point or center.
2. in anatomy, the bone on the outer or thumb side of the forearm.
grid radius grid focus.

ra·di·us

, gen. and pl.

ra·di·i

(rā'dē-ŭs, rā'dē-ī),
1. The lateral and shorter of the two bones of the forearm.
2. A straight line passing from the center to the periphery of a circle.
Synonym(s): radio- (3)
[L. spoke of a wheel, rod, ray]

RADIUS

Obstetrics A study–Routine Antenatal Diagnostic Imaging with Ultrasound–involving 15,000 ♀ that evaluated fetal ultrasonography Conclusion No benefit

ra·di·us

, pl. radii (rā'dē-ŭs, -ī)
1. [TA] The lateral and shorter of the two bones of the forearm.
2. A straight line passing from the center to the periphery of a circle.
[L. spoke of a wheel, rod, ray]

radius

One of the two forearm bones, the other being the ULNA. The radius is on the thumb side and lies parallel to the ulna when the palm is facing forward. When the hand is rotated so that the thumb turns inward, the upper end of the radius rotates on a boss on the lower end of the upper arm bone (HUMERUS) but the lower end crosses over the ulna.

radius

the anterior bone in the lower part of the forelimb of vertebrates. see PENTADACTYL LIMB.

ra·di·us

, pl. radii (rā'dē-ŭs, -ī)
1. [TA] Lateral and shorter of two bones of forearm.
2. Straight line passing from center to periphery of a circle.
[L. spoke of a wheel, rod, ray]