Русско-англо-русский юридический словарь

Voidable, in law, is a transaction or action that is valid but may be annulled by one of the parties to the transaction. Voidable is usually used in distinction to void ab initio (or void from the outset) and unenforceable. (Wikipedia)

In law, severability (sometimes known as salvatorius, from Latin) refers to a provision in a contract which states that if parts of the contract are held to be illegal or otherwise unenforceable, the remainder of the contract should still apply. (Wikipedia)

SALVATORIAN CLAUSE (noun): a clause in a contract that states that if parts of the contract are held to be illegal or unenforceable, the remainder of the contract should still be valid (Macmillan Dictionary)

Consequences of invalidity of agreement. If an agreement purporting to be made under section 21 or section 21A or section 21B is void or is avoided or is invalid or unenforceable (including an agreement set aside under section 21J), the provisions of this Act have effect as if the agreement had never been made. (Property (Relationships) Act 1976, New Zealand Legislation)