What is the meaning of Illegal?

Not authorized by law.

Contrary to or forbidden by law, especially criminal law.

Forbidden by established rules.

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

Being or doing something illegally.

Being an illegal immigrant; residing in a country illegally.

Describing a programming operation that is not allowed by the operating system.

An illegal act or technique.

Contraband, esp. illegal substances such as drugs.

A spy working abroad illegally and undercover, without visible ties to his or her country’s authorities.

Obsolete spelling of ilegal

Source: wiktionary.org

See also