spherical

comparative more spherical · superlative most spherical · alternative archaic sphærical

1. geometryShaped as a sphere; being a sphere.

   The ability of a segment of a glass sphere to magnify whatever is placed before it was known around the year 1000, when the spherical segment was called a reading stone, essentially what today we might term a frameless magnifying glass or plain glass paperweight.

   2013 September-October, Henry Petroski, “The Evolution of Eyeglasses”, in American Scientist

   Synonyms: spheric, spheral, globular, orbicular, round

2. not comparablegeometryOf, or pertaining to, spheres.
3. mathematicsOf a coordinate system, specifying the location of a point in a plane by using a radius and two angles.
4. astrologyOf or relating to the heavenly orbs, or to the sphere or spheres in which, according to ancient astronomy and astrology, they were set.

   Knaves, thieves, and treachers by spherical predominance.

   c. 1603–1606, William Shakespeare, “The Tragedie of King Lear”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act I, scene ii]

5. mathematicsOf a multivariate probability distribution, to have a covariance matrix equal to the identity matrix up to a multiplicative factor.

   a spherical Gaussian distribution