no-knock

[ noh-nok ]

adjective

1. Law. relating to or denoting a policy that authorizes law-enforcement officers to enter premises unannounced and without identifying themselves:

   On the basis of an anonymous tip, the police had obtained a no-knock search warrant for drugs.

2. antiknock.

Word History and Origins

Origin of no-knock¹

An Americanism dating back to 1965–70