- IsCurve
- IsCusp
- IsCuspidal
- IsCyclic
- IsDecomposable
- IsDefault
- IsDeficient
- IsDefined
- IsDefinite
- IsDefinitelyEqual
- IsDefinitelyZero
- IsDegenerate
- IsDelPezzo
- IsDenselyRepresented
- IsDesarguesian
- IsDesign
- IsDiagonal
- IsDifferenceSet
- IsDifferentialField
- IsDifferentialIdeal
- IsDifferentialLaurentSeriesRing
- IsDifferentialOperatorRing
- IsDifferentialSeriesRing
- IsDimensionCompatible
- IsDirected
- IsDirectSum
- IsDirectSummand
- IsDiscriminant
- IsDisjoint
- IsDistanceRegular
- IsDistanceTransitive
- IsDistinguished
- IsDivisible
- IsDivisibleBy
- IsDivisibleBy(a, b) : FldFunElt, FldFunElt -> BoolElt, FldFunElt
- IsDivisibleBy(P, n) : JacHypPt, RngIntElt -> BoolElt, JacHypPt
- IsDivisibleBy(P, n) : PtEll, RngIntElt -> BoolElt, PtEll
- IsDivisibleBy(n, d) : RngIntElt, RngIntElt -> BoolElt, RngIntElt
- IsDivisibleBy(a, b) : RngMPolElt, RngMPolElt -> BoolElt, RngMPolElt
- IsDivisibleBy(f, g) : RngUPolElt, RngUPolElt -> BoolElt, RngUPolElt
- IsDivisionRing
- IsDivisorialContraction
- IsDomain
- IsDominant
- IsDoublePoint
V2.28, 13 July 2023