illegal

il·le·gal
I1L1L1E1G2A1L1
UK/ɪˈliːɡəl/US/ɪˈli.ɡəl/US[ɪɫˈli.ɡəɫ]

adjective

Contrary to, forbidden, or not authorized by law, especially criminal law.

“illegal pilot”

CommonScrabble 8

Meanings

adjectiveillegal (comparative more illegal or (nonstandard or informal) illegaler, superlative most illegal or (nonstandard or informal) illegalest)

comparative more illegal · comparative informal nonstandard illegaler · superlative most illegal · informal nonstandard superlative illegalest

  1. Contrary to, forbidden, or not authorized by law, especially criminal law.

    This is illegal, you know!

    5 more examples

    Nearly 40 million people live in UK areas with illegal air pollution

    Their illegal mining operations in Asia, Africa and elsewhere, are protected by officials and police paid to look the other way – and powerful customers in the construction industry who prefer not to ask too many questions.

    In all times the Princes in England have done ſomething illegal to get Money: But then came a Parliament and all was well, the People and the Prince kiſt and were Friends, and ſo things were quiet for a while.

    a. 1654, John Selden, “Money”, in Table-Talk, 3rd edition, London: Jacob Tonson, published 1716, page 74

    Imagine a country where children do nothing but play until they start compulsory schooling at age seven. Then, without exception, they attend comprehensives until the age of 16. Charging school fees is illegal, and so is sorting pupils into ability groups by streaming or setting.

    2013 July 19, Peter Wilby, “Finland spreads word on schools”, in The Guardian Weekly, volume 189, number 6, archived from the original on 25 Mar 2022, page 30

    Major parties have long relied on large-scale campaign contributions, and the LDP was only recently mired in an illegal fundraising scandal. Sanseito drew its support from smaller, individual donations.

    2025 July 24, Ned Temko, “In Japan, too, voters want their country to be ‘great again’”, in The Christian Science Monitor, archived from the original on 27 Jul 2025

    Synonyms: criminal, felonious, illicit, irregular, crimeful, criminal, illegitimate, illicit · Antonyms: lawful, legal, de jure, lawful, legal, legitimate, licit, rightful

  2. Forbidden by established rules.

    Moving a pawn backward is an illegal move in chess.

    1 more example

    The computer program performed an illegal operation and was terminated.

    Synonyms: banned, disallowed, banned, disallowed, forbidden, impermissible, illicit, interdicted

  3. hobbiesTotally fictitious, and often issued on behalf of a non-existent territory or country.

    Synonyms: bogus

  4. offensivesometimesBeing or doing something illegally.

    illegal pilot

    2 more examples

    illegal immigrant

    illegal logger

  5. USoffensivesometimesBeing an illegal immigrant; residing in a country illegally.

    Synonyms: undocumented

nounillegal (plural illegals)

plural illegals

  1. obsoleteAn illegal act or technique.

    That whatſoever illegals hath been uſed againſt his friends and ſubjects, by impriſoning them without law, or impoſing fines upon their eſtates, be diſclaimed, and that perſons ſo committed be forthwith diſcharged.

    c. 1650, John Spalding, The History of the Troubles and Memorable Transactions in Scotland, from the Year 1624 to 1645, volume II, Aberdeen: T. Evans, published 1792, pages 72–73
  2. colloquialin pluralContraband, esp. illegal substances such as drugs.

    …I've got illegals in my bottom…!

    2004, “Reapercussions”, in Dead Like Me, season 1, episode 4, spoken by Mason (Callum Blue)
    1 more example

    “Here’s what I could do,” Eve supposed. “I could slap your head against that wall, while I’m kicking your balls into your belly,” she added to the companion. “And after that, I can have you in restraints while I turn out your pockets. You’re carrying illegals.

    2008, J. D. Robb [pseudonym; Nora Roberts], Strangers in Death, Penguin, →ISBN
  3. abbreviationcolloquialellipsisoffensiveEllipsis of illegal immigrant.

    In Manchester and in Aldershot in Hampshire, asylum seeker accommodation was targeted by demonstrators carrying placards that read “deport them, don’t support them” and “no apartments for illegals”.

    2024 August 1, Josh Halliday, Neha Gohil, “Police in England urged to protect mosques as far right plans more rallies”, in The Guardian, archived from the original on 24 Aug 2024

    Synonyms: crimmigrant

  4. espionageA spy operating abroad illegally and under non-official cover, without visible ties to his or her country’s authorities.

    Anna Chapman, whose glamorous appearance won her more publicity in the Western media than all the other illegals combined, was so successfully deceived by a US sting operation that she handed over her SVR laptop to an FBI agent posing as a Russian.

    2012, Christopher Andrew, ‘Colder War’, Literary Review, number 399
    1 more example

    Traditionally, illegals have been extremely hard for counterintelligence agencies to find, but in a world of biometric data, facial recognition software and open source investigation possibilities, it has become harder for Russia to keep its illegals below the radar.

    2022 August 26, Shaun Walker, “Socialite who charmed Nato staff in Naples was Russian spy, say investigators”, in The Guardian, archived from the original on 01 Oct 2022

Synonyms & antonyms

adjectiveTotally fictitious, and often issued on behalf of a non-existent territory or country.

Similar

adjectiveBeing an illegal immigrant; residing in a country illegally.

nounEllipsis of illegal immigrant.

More synonyms by meaning

adjectiveprohibited by law or by official or accepted rules

Opposite

Synonym sets from Open English WordNet, CC BY 4.0.

Origin

  1. Latinlegalis
  2. Medieval Latinillegalis
  3. Frenchillégal
  4. Englishillegal

Borrowed from French illégal, from Medieval Latin illegalis, from Latin legalis, by surface analysis, il- + legal. In senses relating to immigration, via clipping of illegal alien or illegal immigrant.

Full word history & related roots →

Translations

Ancient Greek παράνομος, ἀθέμιτος
  • παράνομος (paránomos)contrary to or forbidden by law
  • ἀθέμιτος (athémitos)contrary to or forbidden by law
  • παράνομος (paránomos)prohibited by established rules
Arabic غَيْر قَانُونِيٍّ
  • غَيْر قَانُونِيٍّ (ḡayr qānūniyyin)contrary to or forbidden by law
Bulgarian незаконен, нелегален
  • незаконен (nezakonen)contrary to or forbidden by law
  • нелегален (nelegalen)contrary to or forbidden by law
  • забранен (zabranen)prohibited by established rules
Catalan il·legal, il·legal
  • il·legalcontrary to or forbidden by law
  • il·legalprohibited by established rules
Chinese Mandarin 非法的, 不合法的
  • 非法的 (fēifǎ de)contrary to or forbidden by law
  • 不合法的 (bùhéfǎ de)contrary to or forbidden by law
  • 不法的 (bùfǎ de)contrary to or forbidden by law
  • 禁止的 (jǐnzhǐ de)prohibited by established rules
  • 卧底 (wòdǐ)undercover spy
Czech ilegální, nezákonný
  • ilegálnícontrary to or forbidden by law
  • nezákonnýcontrary to or forbidden by law
Dutch strafbaar, illegaal
  • strafbaarcontrary to or forbidden by law
  • illegaalcontrary to or forbidden by law
  • onwettigcontrary to or forbidden by law
Esperanto kontraŭleĝa
  • kontraŭleĝacontrary to or forbidden by law
Estonian ebaseaduslik, illegaalne
  • ebaseaduslikcontrary to or forbidden by law
  • illegaalnecontrary to or forbidden by law
  • seadusvastanecontrary to or forbidden by law
Finnish laiton, lainvastainen
  • laitoncontrary to or forbidden by law
  • lainvastainencontrary to or forbidden by law
  • sääntöjen vastainenprohibited by established rules
French illégal, interdit
  • illégalcontrary to or forbidden by law
  • interditprohibited by established rules
  • défenduprohibited by established rules
  • espion infiltréundercover spy
  • agent clandestinundercover spy
German illegal, rechtswidrig
  • illegalcontrary to or forbidden by law
  • rechtswidrigcontrary to or forbidden by law
  • illegalprohibited by established rules
Greek παράνομος, έκνομος
  • παράνομος (paránomos)contrary to or forbidden by law
  • έκνομος (éknomos)contrary to or forbidden by law
  • άνομος (ánomos)contrary to or forbidden by law
  • παράνομος (paránomos)prohibited by established rules
  • απαγορευμένος (apagorevménos)prohibited by established rules
Hawaiian kū ʻole i ke kānāwai, mawaho o ke kānāwai
  • kū ʻole i ke kānāwaicontrary to or forbidden by law
  • mawaho o ke kānāwaicontrary to or forbidden by law
Hebrew בלתי חוקי, אָסוּר
  • בלתי חוקי (biltí khukí)contrary to or forbidden by law
  • אָסוּר (asúr)prohibited by established rules
Hindi अवैध, ग़ैरक़ानूनी
  • अवैध (avaidh)contrary to or forbidden by law
  • ग़ैरक़ानूनी (ġairqānūnī)contrary to or forbidden by law
  • ख़िलाफ़क़ानून (xilāfqānūn)contrary to or forbidden by law
Hungarian illegális
  • illegáliscontrary to or forbidden by law
Icelandic ólöglegur
  • ólöglegurcontrary to or forbidden by law
Irish neamhdhleathach, aindleathach
  • neamhdhleathachcontrary to or forbidden by law
  • aindleathachcontrary to or forbidden by law
  • mídhleathachcontrary to or forbidden by law
  • neamhdhlíthiúilcontrary to or forbidden by law
Italian illegale
  • illegalecontrary to or forbidden by law
Japanese 不法の, 違法の
  • 不法の (fuhō no)contrary to or forbidden by law
  • 違法の (ihō no)contrary to or forbidden by law
  • 違法の (ihō no)prohibited by established rules
Korean 불법적인, 반칙의
  • 불법적인 (bulbeopjeog-in)contrary to or forbidden by law
  • 반칙의 (banchigui)prohibited by established rules
Latin illicitus, speculator
  • illicituscontrary to or forbidden by law
  • speculatorundercover spy
  • explorator occultusundercover spy
Latvian pretlikumīgs
  • pretlikumīgscontrary to or forbidden by law
Lithuanian neteisėtas
  • neteisėtascontrary to or forbidden by law
Malay haram
  • haramcontrary to or forbidden by law
Māori turekore, turekore
  • turekorecontrary to or forbidden by law
  • turekoreprohibited by established rules
Norwegian Bokmål ulovlig, forbudt
  • ulovligcontrary to or forbidden by law
  • forbudtcontrary to or forbidden by law
  • lovstridigcontrary to or forbidden by law
  • illegalcontrary to or forbidden by law
  • ulovligprohibited by established rules
Polish nielegalny, nielegał
  • nielegalnycontrary to or forbidden by law
  • nielegałundercover spy
Portuguese ilegal, ilegal
  • ilegalcontrary to or forbidden by law
  • ilegalprohibited by established rules
  • proibidoprohibited by established rules
Romanian ilegal, nelegal
  • ilegalcontrary to or forbidden by law
  • nelegalcontrary to or forbidden by law
  • ilegalprohibited by established rules
Russian незако́нный, нелега́льный
  • незако́нный (nezakónnyj)contrary to or forbidden by law
  • нелега́льный (nelegálʹnyj)contrary to or forbidden by law
  • неправоме́рный (nepravomérnyj)contrary to or forbidden by law
  • непра́вильный (neprávilʹnyj)prohibited by established rules
  • неве́рный (nevérnyj)prohibited by established rules
  • нелега́л (nelegál)undercover spy
Slovak ilegálny, nezákonný
  • ilegálnycontrary to or forbidden by law
  • nezákonnýcontrary to or forbidden by law
Spanish ilegal, ilegal
  • ilegalcontrary to or forbidden by law
  • ilegalprohibited by established rules
  • espía encubiertoundercover spy
  • topoundercover spy
Swahili haramu, haramu
  • haramucontrary to or forbidden by law
  • haramuprohibited by established rules
Swedish olaglig, illegal
  • olagligcontrary to or forbidden by law
  • illegalcontrary to or forbidden by law
  • lagstridigcontrary to or forbidden by law
  • förbjudenprohibited by established rules
  • otillåtenprohibited by established rules
Thai ที่ผิดกฎหมาย
  • ที่ผิดกฎหมาย (Thī̀ p̄hid kḍh̄māy)contrary to or forbidden by law
Turkish yasa dışı, illegal
  • yasa dışıcontrary to or forbidden by law
  • illegalcontrary to or forbidden by law
Ukrainian незако́нний, нелега́льний
  • незако́нний (nezakónnyj)contrary to or forbidden by law
  • нелега́льний (nelehálʹnyj)contrary to or forbidden by law
Urdu غیرقانونی, ناجائز
  • غیرقانونی (ġairqānūnī)contrary to or forbidden by law
  • ناجائز (nājaiz)contrary to or forbidden by law
Vietnamese bất hợp pháp, trái phép
  • bất hợp phápcontrary to or forbidden by law
  • trái phépcontrary to or forbidden by law
Welsh anghyfreithlon, anghyfreithiol
  • anghyfreithloncontrary to or forbidden by law
  • anghyfreithiolcontrary to or forbidden by law

Rhymes & wordplay

Rhymes with illegal

All rhymes →
Cite this entry
APA

illegal. (n.d.). In WatkinsX Dictionary. Retrieved November 2, 2026, from https://dictionary.watkinsx.com/word/illegal

MLA

“illegal.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/illegal. Accessed November 2, 2026.

Chicago

WatkinsX Dictionary, s.v. “illegal,” accessed November 2, 2026, https://dictionary.watkinsx.com/word/illegal.

Source: illegal on Wiktionary, CC BY-SA 4.0.