Someone who's a perfectly smooth bastard no matter which way you look at him.
Also works with Spherical nutjob, spherical jackass.
Syntax: Spherical cuss-word
History: Often attributed to the eccentric Swiss Astronomer Fritz
Zwicky, who used to refer to fellow astronomers at
the Mt. Wilson Observatory as Spherical Bastards. "Because", in his words, "they were bastards, when looked at from any side".
Source: dynamical-systems.org/
zwicky/Zwicky-e.html