From Longman Dictionary of Contemporary Englishgrand juryˌgrand ˈjury noun [countable] lawSCT a group of people in the US who decide whether someone charged with a crime should be judged in a court of law —grand juror noun [countable]
Examples from the Corpus
grand jury• Appearing before a grand jury under subpoena as Bowles did does not imply guilt.• Being called before a grand jury does not mean a witness has done anything wrong.• Starr had argued that there never should be a right to such secrecy in the face of a grand jury subpoena.• Would be under indictment by every grand jury south of the Potomac.• He was a member of the Shropshire grand jury and frequently acted on behalf of his parish in legal matters.• A subsequent grand jury said there was insufficient evidence of misconduct.• There is no indication that Leckie has testified before the grand jury.From Longman Business Dictionarygrand juryˌgrand ˈjuryLAW a jury in the US that looks at a case that could be brought against someone and decides whether it is strong enough to continue withA grand jury last month indicted the former director of the firm on two counts of perjury. → jury 