Not either. See either.Not one or the other. See either, pron.Not either; not in either case: a disjunctive conjunction (the negative of either), preceding one of a series of two or more alternative clauses, and correlative with nor (or, formerly, neither or ne) before the following clause or clauses.Not in any case; in no case; not at all: used adverbially for emphasis at the end of the last clause, when this already contains a negative.And not; nor yet.