nullity

n.

（尤指婚姻）法律上无效；不存在；无足轻重的人；

复数：nullities

1. The aggregate of human knowledge , as compared with what is to be learned , is a mere nullity.
   人类聚集之知识

On the nullity of graphs
The nullity of unicyclic graphs
On the nullity of bicyclic graphs
Trees with maximum nullity
On the nullity of unicyclic graphs ☆
On the nullity of line graphs of trees
Contact metric manifolds satisfying a nullity condition
Theorems on ascent, descent, nullity and defect of linear operators
Perturbation theory for nullity, deficiency and other quantities of linear operators
The Bordering Algorithm and Path Following Near Singular Points of Higher Nullity