Definition of nilpotent:
(adj) :
(mathematics, algebra, ring theory, of an element x of a ring) Such that, for some positive integer n, xⁿ = 0.
(adj) :
(mathematics, algebra) In any of several technical senses: behaving analogously to nilpotent ring elements as an element of some other algebraic structure; composed of elements displaying such behavior.
(adj) :
(ring theory, of an ideal I) Such that there exists a natural number k with Iᵏ = 0.
(adj) :
(group theory, of a group) Admitting a central series of finite length.
(adj) :
(Lie theory, of an element x of a Lie algebra L) Belonging to the derived algebra of L and such that the adjoint action of x is nilpotent (as a linear transformation on L).
(adj) :
(Lie theory, of a Lie algebra) Such that the lower central series terminates.