Definition/Meaning  Word/Phrase 
joint between the distal end of the radius and the proximal row of carpal bones 
articulatio radiocarpea
,
carpus
,
radiocarpal joint
,
wrist
,
wrist joint

reliable and deadly 15,000pound fragmentation bomb that explodes just above ground with a large radius; the largest conventional bomb in existence; used in Afghanistan 
Big Blue
,
BLU82

circle that touches a curve (on the concave side) and whose radius is the radius of curvature 
circle of curvature
,
osculating circle

handsaw with a long narrow blade for cutting short radius curves; similar to a compass saw 
keyhole saw

unit of plane angle adopted under the Systeme International d'Unites; equal to the angle at the center of a circle subtended by an arc equal in length to the radius (approximately 57.295 degrees) 
rad
,
radian

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

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

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

angle subtended by the mean equatorial radius of the Earth at a distance of one astronomical unit 
solar parallax

flying downward in a helical path with a large radius 
spiral
