This is the type of a quotient of a tensor algebra by a two-sided ideal.
At this point, one cannot define quotients of quotients.
The object NCQuotientRing is a type, with ancestor classes NCRing < Ring < Type < MutableHashTable < HashTable < Thing.
The source of this document is in /build/reproducible-path/macaulay2-1.25.05+ds/M2/Macaulay2/packages/NCAlgebra/NCAlgebraDoc.m2:275:0.