Is There a Smart Casual in the Workplace?

It's so interesting how more formal attire has now moved from the typical thing in the workplace to selected places in our free time. I was recently at the symphony and I noticed the mix of people who dress up completely changed. Used to be 50% jeans, 50% a little more formal. Now I think it's more like 70, 30, 80, 20 or so. There's a smart casual and many people have different interpretations of what smart casual means. It allows for a lot more expression.