Non-disclosure agreements (NDA's) are agreements that some employers pressure employees to sign, to prevent them talking about things that might be embarrassing to the employers. Philip Green used them to prevent employees speaking out on allegations of sexual harassment and racism, but Lord Hain used Parliamentary privilege to identify him in the Lords.
Labour are opposed to NDA's aren't they? But now Jeremy Corbyn is using NDAs to prevent Labour party staff from speaking out on allegations of anti-semitism in the party. This man is a complete disaster zone IMO, he will lead Labour to oblivion.