Prohibited by official rules: an illegal pass in football. (adjective)
Unacceptable to or not performable by a computer: an illegal operation. (adjective)
An illegal immigrant.(noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "illegal" in a sentence
"Calling illegal immigrants 'undocumented workers' does not lessen the fact that they are * illegal*, that they have broken our laws and should be treated as such."
"In terms of language, one of the toughest battles today is over the widespread use of the term "illegal immigrant," made popular by conservatives in an attempt to dehumanize undocumented immigrants."
"For those entering illegally, the term illegal immigrant is preferred."