fill a/the void
To replace someone or something that is absent or missing. No, we got that project done—Rebecca filled the void while you were on vacation. If Mike doesn't play sports this year, what will fill the void besides his trouble-making friends?
null and void
No longer valid, legitimate, or enforceable. This contract shall be rendered null and void immediately should either party fail to fulfil their obligations.
null and void
Cliché without legal force; having no legal effect. The court declared the law to be null and void. The millionaire's will was null and void because it was unsigned.
null and void
Canceled, invalid, as in The lease is now null and void. This phrase is actually redundant, since null means "void," that is, "ineffective." It was first recorded in 1669.
ˌnull and ˈvoid
(formal) (of a legal agreement) no longer effective or valid: The contract was declared null and void.