isopycnic

Relating to or indicating equality of density: as, an isopycnic line.

A line or surface, in a substance or medium, at every point of which the density is the same. Also isopyc.

A line or surface passing through those points in a medium, at which the density is the same.

Having equal density, as different regions of a medium; passing through points at which the density is equal.

(of points on a surface, or in a medium) having equal densities

A line on a chart connecting points of equal density