B1[C or U]a rule, usually made by a government, that is used to order the way in which a society behaves, or the whole system of such rules: There are laws against drinking in the street.The laws governing the possession of firearms are being reviewed.They led the fight to impose laws on smoking.They have to provide a contract by law.She's going to study law at university.[or+ -ing verb+ to infinitive]Many doctors backed plans for a law banning/to ban all tobacco advertising.→ See alsobylaw, lawsuit, lawyerRules and lawsthe lawB2the system of rules of a particular country: What does the law say about having alcohol in the blood while driving?Of course robbery is against the law!The judge ruled that the directors had knowingly broken the law.You can't take that course of action and remain within the law.Rules and laws›[S]informalthe police: The law was/were out in force at the demonstration.The police generallygo to law›When someone goes to law about something, they ask a court to make a legal judgment about it.Taking legal action