1) Globosity 2) Globularness 3) Rotundity 4) Roundness 5) Sphericalness 1) Globosity 2) Globularness 3) Rotundity 4) Sphericalness 
• (n.) The quality or state of being spherial; roundness; as, the sphericity of the planets, or of a drop of water.
Sphe·ric'i·ty noun [ Confer French sphéricité .] The quality or state of being spherial; roundness; as, the sphericity of the planets, or of a drop of water. 
[n] - the roundness of a 3-dimensional object
sphericalness noun the roundness of a 3-dimensional object
A descriptive term to describe how close a particle