Nullity

[Sarah]

Nonexistence; as, a decree of nullity of marriage is a decreethat no legal marriage exists.

[Sarah]

A stupid attempt to make it possible to divide by zero. Any number divided by 0 yields nullity. Any number multiplied with/divided by/added to/substracted from nullity yields nullity.

[Renato]

something such as an agreement or decision which no longer has legal force:

[Lizzy Liz]

An act or thing that is legally void.