nebulosity

noun, plural neb·u·los·i·ties.

1. nebulous or nebular matter.
2. a nebulous form, shape, or mass.
3. the state or condition of being nebulous.

noun plural -ties

1. the state or quality of being nebulous
2. astronomy a nebula

n.1738, from French nébulosité, from Late Latin nebulositatem (nominative nebulositas), from Latin nebulosus, from nebula (see nebula).