What does "illegal" mean?
An illegal act or technique.
Illegal
/ɪˈli.ɡəl/ adj, noun, slang
adj, noun, slang ·Common ·Middle school level
Meaning at a glance
- Primary sense: An illegal act or technique.
- Grammar: illegal is listed as adj, noun, slang.
- Nearest alternatives: aberrant, abnormal, abominable, actionable.
- Useful contrasts: aboveboard, allowable, authorized.
- Usage evidence: Everybody took a hostile attitude toward illegal aliens.
How to use "illegal"
- Start with the primary definition, then check the part of speech before placing the word in a sentence.
- Compare nearby synonyms to make sure "illegal" carries the exact meaning, tone, and strength you need.
- Use the example sentence as a context check. If your sentence uses the word differently, confirm that the grammar still fits.
Meaning check
- Does the word fit the sentence's grammar?
- Does it match the intended tone rather than only the dictionary definition?
- Would a simpler synonym be clearer for the reader?
- Is there enough surrounding context to prevent ambiguity?
Source and review context
This entry combines structured lexical data with WordToolSet review checks. Definitions, examples, synonyms, and usage notes may come from different source tables, so the page is designed to show evidence from more than one angle before you rely on "illegal" in a final draft.
If a word has several senses, prefer the sense that matches your sentence's grammar and surrounding context. A correct definition can still be the wrong choice when the sentence needs a different register, emphasis, or level of specificity.
Before you rely on this definition
Read the first definition as a starting point, then check the example, synonyms, and part of speech before treating "illegal" as the right word for your sentence.
If your draft is formal, technical, persuasive, or sensitive, compare "illegal" with a nearby alternative so the final choice matches both meaning and reader expectation.
Compare nearby meanings
- Use synonyms when you need a softer, stronger, simpler, or more specific word.
- Use antonyms to check the boundary of the meaning and avoid accidental contrast.
- Use the example sentence to confirm the word behaves naturally in context.
- Keep the original wording when a replacement adds complexity without improving precision.
Definition decision workflow
1. Identify the role
Check whether "illegal" is acting as adj, noun, slang in your sentence. A definition is only useful when the grammar matches the way the word is being used.
2. Test the nearest option
Compare it with "aberrant" and other nearby choices to see whether the sentence needs a softer, stronger, or more familiar word.
3. Confirm with context
Use the example sentence below as an evidence check, then read your own sentence out loud to catch tone or rhythm problems.
Review note: Definition pages are checked for source coverage, sentence evidence, synonym support, and editorial insight before they are treated as approval-ready pages. If the evidence is too thin, the page remains available to users but is kept out of the approval-facing indexed inventory.
Final meaning check
Before publishing a sentence with "illegal", ask whether the word helps the reader understand the idea faster. A precise word should reduce confusion, not simply make the sentence look more polished.
When the definition, synonym evidence, and example context point in the same direction, the word is usually a safer choice. When they conflict, revise the sentence or choose a clearer alternative.
Definitions
Noun
- 1 An illegal act or technique. obsolete
"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."
- 2 Contraband, esp. illegal substances such as drugs. colloquial, in-plural
"…I've got illegals in my bottom…!"
- 3 An illegal immigrant. colloquial, offensive
"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”."
- 4 A 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."
Adjective
- 1 Contrary to, forbidden, or not authorized by law, especially criminal law.
"This is illegal, you know!"
- 2 Forbidden by established rules.
"Moving a pawn backward is an illegal move in chess."
- 3 Totally fictitious, and often issued on behalf of a non-existent territory or country.
- 4 Being or doing something illegally. offensive, sometimes
"illegal immigrant"
- 5 Being an illegal immigrant; residing in a country illegally. US, offensive, sometimes
Adjective
- 1 prohibited by law or by official or accepted rules wordnet
Synonyms
All synonymsAntonyms
Example
"Everybody took a hostile attitude toward illegal aliens."
Common questions
What is a synonym for "illegal"?
Common synonyms include: aberrant, abnormal, abominable, actionable, adulterine, against the law.
How do you use "illegal" in a sentence?
Everybody took a hostile attitude toward illegal aliens.
How do you pronounce "illegal"?
Pronounced /ɪˈli.ɡəl/.
Etymology
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.