Casual Work Days - Common Mistakes - as part of the expert series by GeoBeats. If you look up the word "casual" you might be surprised by its definition. It is defined as feeling or showing little concern, or lacking a high degree of interest or devotion. If these words were written on your shirt, you probably would not have a job for long. People have taken casual day to a whole new extreme. If you would wear it to a club, do not wear it to work. It is better to go above the bar, rather than below it. So try and keep your standards up. Common faux pas are wearing clothes that are too tight, ripped, flip-flops, floppy, no belt, cleavage-bearing shirt and inappropriate jewelry. Before you put it on, ask yourself this: if the CEO, president and board of the directors ask you to come to the conference room that day, would you feel confident with the outfit you had picked out for that casual day?