Definition:-

• Relaxed and unconcerned. (adjective)
• Not regular or permanent. (adjective)
• Happening by chance; accidental. (adjective)
• Without formality of style or manner, in particular (of clothing) suitable for everyday wear rather than formal occasions. (adjective)
• A person who does something irregularly. (noun)
• Clothes or shoes suitable for everyday wear rather than formal occasions. (noun)
• A youth belonging to a subculture characterized by the wearing of expensive casual clothing and frequently associated with football hooliganism. (noun)