Definitions

1. adjective

not permitted by law or official rules; forbidden

“The sale of fireworks is illegal in this city.”

2. noun

an act or instance of doing something that is not permitted by law or official rules

“The company was fined for one of its illegal activities.”

3. adverb

in a manner that is not permitted by law or official rules

“She worked illegally long hours to meet the deadline.”

4. verb

to make or declare something to be against the law

“The politician vowed to illegalize the production of certain chemicals.”