Abolish as a verb:
To end a law, system, institution, custom or practice.
"Slavery was abolished in the nineteenth century."
Abolish as a verb (archaic):
To put an end to or destroy, as a physical object; to wipe out.
Nullify as a verb (transitive, legal):
to make legally invalid.
"The contract has been nullified."
Nullify as a verb:
to prevent from happening