casual - adjective

• marked by blithe unconcern
• without or seeming to be without plan or method; offhand
• appropriate for ordinary or routine occasions
• occurring or appearing or singled out by chance
• hasty and without attention to detail; not thorough
• occurring from time to time
• characterized by a feeling of irresponsibility
• natural and unstudied
• not showing effort or strain

casual - thesaurus

chance   cursory   daily   effortless   everyday   fooling   insouciant   nonchalant   occasional   passing   perfunctory