sphere

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sphere

 [sfēr]
a three dimensional round body; called also globus. adj., adj spher´ical.
attraction sphere centrosome.
segmentation sphere
1. morula.

sphere

(sfēr),
A ball or globular body.
[G. sphaira]

sphere

(sfēr)
A ball or globular body.
[G. sphaira]

sphere 

A term commonly used to denote the spherical component of a prescription or of the power of a lens, or even a spherical lens. See spherical lens; prescription.
far point sphere The imaginary spherical surface on which lie the far points of accommodation for all directions of gaze. See far point of accommodation.
near point s . The imaginary spherical surface on which lie the near points of accommodation for all directions of gaze. See near point of accommodation.
References in periodicals archive ?
Two great circles [C.sub.1] and [C.sub.2] of two distinct great 2-spheres of [S.sup.3] are called complementary if there is a coordinate system in which they can be represented as
Note that if R and t are held constant (say R = a and t = [t.sub.0]) the line-element reduces to that of a 2-sphere with radius a > 2m.
To justify Property (c), consider an embedded 2-sphere [S.sup.2] [subset] [M.sub.1].
In Section 2, we define Brouwer degree for polynomial self-maps [S.sup.2](R) [right arrow] [S.sup.2](R) of the 2-sphere [S.sup.2](R) over R and show that if R contains the field of algebraic real numbers [R.sub.alg], then the polynomials P and Q of the matrices [[gamma].sup.p], for p an odd integer, can be taken in [R.sub.alg][X, Y, Z], so the matrices are hermitian for R = Q, the field of algebraic numbers.
The spatial components of equations (3) describe a sphere of radius [R.sub.c](r)=|r -[r.sub.0]|, centred at a point located anywhere on the 2-sphere [r.sub.0].