In this paper we study some properties of the class of nu-quasi-ordinary
hypersurface singularities. They are defined by a very mild condition on its
(projected) Newton polygon. We associate with them a Newton tree and
characterize quasi-ordinary hypersurface singularities among nu-quasi-ordinary
hypersurface singularities in terms of their Newton tree. A formula to compute
the discriminant of a quasi-ordinary Weierstrass polynomial in terms of the
decorations of its Newton tree is given. This allows to compute the
discriminant avoiding the use of determinants and even for non Weierstrass
prepared polynomials. This is important for applications like algorithmic
resolutions. We compare the Newton tree of a quasi-ordinary singularity and
those of its curve transversal sections. We show that the Newton trees of the
transversal sections do not give the tree of the quasi-ordinary singularity in
general. It does if we know that the Newton tree of the quasi-ordinary
singularity has only one arrow.Comment: 32 page