- forbidden by law or statute.
- contrary to or forbidden by official rules, regulations, etc.: The referee ruled that it was an illegal forward pass.
- Informal: Disparaging and Offensive. illegal alien.
Origin of illegal
SynonymsSee more synonyms on Thesaurus.com
1. unlawful; illegitimate; illicit; unlicensed.
1, 2. Illegal, unlawful, illegitimate, illicit, criminal can all describe actions not in accord with law. Illegal refers most specifically to violations of statutes or, in organized athletics, codified rules: an illegal seizure of property; an illegal block ( in football ). Unlawful means not sanctioned by or according to law: an unlawful claim to the inheritance; to take unlawful advantage of the trading situation. Illegitimate means lacking legal or traditional right or rights: an illegitimate child; illegitimate use of privileged knowledge. Illicit, which originally meant simply “not permitted,” now most often applies to matters regulated by law with specific emphasis on the way things are carried out: illicit conversion of property; an illicit attempt to control the market. Criminal most often refers to violation of the statutes of penal as opposed to civil law. All felonies are criminal as are all crimes sometimes punishable by death such as murder, arson, and kidnapping: a criminal act.
3. See illegal alien.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for illegal
Watching him now being accused of illegal operations will not see them shedding any tears.Annoying Airport Delays Might Prevent You From Becoming the Next AirAsia 8501
January 6, 2015
In March, police arrested a group of wealthy businessmen and government officials who were about to dine on illegal tiger meat.China’s Internet Is Freer Than You Think
December 27, 2014
This would take time since, under current law, even scouting Cuban baseball players on the island is illegal.Is Major League Baseball Ready For Cuba’s Players?
December 19, 2014
The lawyers decided to stay in Chechnya and demand investigation of illegal actions against them and their office.Putin’s Favorite Acolyte Terrorizes Human Rights Activists
December 14, 2014
Surenos are told when to workout, who to associate with and how to distribute any funds they make from illegal activity.The Mexican Mafia Is the Daddy of All Street Gangs
December 11, 2014
With a man of that sort scrupulousness was a misplaced and even an illegal sentiment.The Secret Agent
They'll do their best to get him, and if they do there'll be trouble of an illegal nature.The Gentleman From Indiana
After all persuasions had failed, we had tried threats: the thing he purposed to do was illegal.Lotus Buds
He had no wish to be discovered there—his entrance had been too irregular, too illegal, for that.The Film of Fear
That is to say, somewhere and at some time there has been a transfer of that property that was illegal.Thankful's Inheritance
Joseph C. Lincoln
- forbidden by law; unlawful; illicit
- unauthorized or prohibited by a code of official or accepted rules
- a person who has entered or attempted to enter a country illegally
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for illegal
Online Etymology Dictionary, © 2010 Douglas Harper