Q: What does "cocktail dress" mean these days? I've been invited to a cocktail party for the first time in at least several years and don't know what to wear in this world of casual Fridays and other days.

A: Wear something you wouldn't wear to work--whether because it's too bare or sparkly or lacy or slinky or satiny. It can be a dress or a suit. It can be a skirt or a pair of pants with a top, long or short, as long as the cut or fabric or applied decoration would look out of place at the office. Test: Imagine wearing the outfit you have in mind to work. If people would say: "Wow! Where are YOU going?" you're on the right track. (On the other hand, it shouldn't be fancy enough for the Oscars.)

Now that even stuffy old-line law firms are going casual--because their dot-com clients think anybody in a suit is a stiff who doesn't get it--some people think there's no point in dressing up for anything. You see sweatpants at funerals and polo shirts at weddings. So think about why you dress up for a special occasion: Not because some rule says you have to, but as a way of marking the difference between everyday life and something more solemn or more joyful and, either way, more singular. By wearing clothes you wouldn't wear to work (or to clean out your gutters) you express respect for the occasion and you actually contribute to its feeling of specialness.

Patricia McLaughlin is a nationally syndicated fashion columnist.
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