What is the meaning of casual?

adjective

• Marked by blithe unconcern.
  • usage: "an ability to interest casual students"; "showed a casual disregard for cold weather"; "an utterly insouciant financial policy"; "an elegantly insouciant manner"; "drove his car with nonchalant abandon"; "was polite in a teasing nonchalant manner"
  • synonyms: insouciant, nonchalant
• Without or seeming to be without plan or method; offhand.
  • usage: "a casual remark"; "information collected by casual methods and in their spare time"
• Appropriate for ordinary or routine occasions.
  • usage: "casual clothes"; "everyday clothes"
  • synonyms: everyday, daily
• Occurring or appearing or singled out by chance.
  • usage: "seek help from casual passers-by"; "a casual meeting"; "a chance occurrence"
  • synonyms: chance
• Hasty and without attention to detail; not thorough.
  • usage: "a casual (or cursory) inspection failed to reveal the house's structural flaws"; "a passing glance"; "perfunctory courtesy"
  • synonyms: cursory, passing, perfunctory
• Occurring from time to time.
  • usage: "casual employment"; "a casual correspondence with a former teacher"; "an occasional worker"
  • synonyms: occasional
• Characterized by a feeling of irresponsibility.
  • usage: "a broken back is nothing to be casual about; it is no fooling matter"
  • synonyms: fooling
• Natural and unstudied.
  • usage: "using their Christian names in a casual way"; "lectured in a free-and-easy style"
  • synonyms: free-and-easy
• Not showing effort or strain.
  • usage: "a difficult feat performed with casual mastery"; "careless grace"
  • synonyms: effortless