Definition of illegal in English:



  • Contrary to or forbidden by law, especially criminal law.

    ‘illegal drugs’
    • ‘I have also seen loads of illegal dumping and it's vandalism of a natural amenity.’
    • ‘English law makes illegal a contract to indemnify a person in respect of liability for fraud.’
    • ‘He thinks it will be difficult to prove it is his voice on the bootleg, illegal version.’
    • ‘They need to be believe that illegal activity is going on in premises before searching them.’
    • ‘No Court will lend its aid to a man who founds his cause of action upon an immoral or an illegal act.’
    • ‘Taking any other type of drug is also an illegal activity so surely one can lead to the other.’
    • ‘We offer advice on the procedures to get court orders to remove illegal encampments.’
    • ‘The line between vigorous price competition and illegal predation may be a fine one.’
    • ‘So it was cruel of York police to choose this week to announce a major crackdown on illegal driving.’
    • ‘If it cannot protect them from drugs then it should protect them from illegal drugs and gangsters.’
    • ‘Swindon Council has had to take action against illegal camps in the town in the past.’
    • ‘He was charged with possession of illegal substances and a public order offence.’
    • ‘The use of this illegal extension currently involves a form of religious gathering.’
    • ‘It is one of the biggest cases of Internet piracy and illegal copying ever discovered.’
    • ‘Many illegal drugs have to be imported into this country from different parts of the world.’
    • ‘Anyone found with illegal substances in their bloodstream will face prosecution.’
    • ‘He was sentenced to four years for illegal possession of the firearm with intent to endanger life.’
    • ‘When we looked into it a number of computers were generating lots of illegal traffic.’
    • ‘The report also raises concerns over the efforts to tackle illegal drug use in prison.’
    • ‘Further the use of cluster bombs as indiscriminate weapons is also illegal it is contended.’
    unlawful, illicit, illegitimate, against the law, criminal, lawbreaking, actionable, felonious
    foul, against the rules
    View synonyms


North American
  • A person living in a country without official authorization.

    • ‘No wonder Tyson and so many other companies like them are hiring so many illegals and claiming that no Americans want these jobs.’
    • ‘Have a telephone tip line to report illegals to Immigration.’
    • ‘But whether illegals are the sort of immigrants he really wants to attract is another matter.’
    • ‘That way you can't tell by looking at the books how many illegals are getting organs - or even that it's going on at all.’
    • ‘Immigration officials say those illegals come from more than 100 countries.’
    • ‘Others may not wish to increase legal immigration without first cutting back on the illegals.’
    • ‘People who insist that all illegals be deported have an excellent point, and I think they're right.’
    • ‘Sales tax, maybe, but most illegals are going to be paid under the table in cash, with the IRS not seeing the details.’
    • ‘The president has expressed his support for amnesty on some occasions for illegals, much to the chagrin of many in the party.’
    • ‘It's really about illegal immigration and how to make illegals legal.’
    • ‘Another gain for illegals is the campaign to allow them to attend state universities at the in-state resident rate.’
    • ‘Irish immigration centres estimate 10,000 Irish are among 14 million illegals in the US.’
    • ‘These poor illegals, mostly of them are Mexican, and they are not coming into this country to do anything other than find a job.’
    • ‘The large number of births to illegals shows that the longer illegal immigration is allowed to persist, the harder the problem is to solve.’
    • ‘Even politicians who thunder about illegals have trouble sticking to their convictions.’
    • ‘I've got another one $1 that a poll would reveal that most Americans would like all illegals deported.’
    • ‘Letting the states bill the Feds for the costs associated with illegals would hit the politicians in the wallet.’
    • ‘By talking tough on illegals, politicians have been able to defend high levels of legal immigration.’
    • ‘Instead, for whatever reason, the Democrats want to have illegals here to use as political pawns.’
    • ‘Before the election a figure for the number of illegals was politically embarrassing because it showed that the government had lost control of our borders.’


Illegal and unlawful have slightly different meanings, although they are often used interchangeably. Something that is illegal is against the law, whereas an unlawful act merely contravenes the rules that apply in a particular context. Thus handball in soccer is unlawful, but it is not illegal. A third word with a similar meaning is illicit: this tends to encompass things that are forbidden or disapproved of by custom or society, as in an illicit love affair


Early 17th century: from French illégal or medieval Latin illegalis, from Latin in- not + legalis according to the law.