If your dress shirt has some form of spread or point collar — which, if you’re wearing a tie, it almost certainly does — then you’re not wearing a button-down shirt at all. You’re actually wearing a ...

thinner faces), or the more casual button-down collar, medium-sized point-collar dress shirts can easily look just as good with a navy blue suit and a tie as they do untucked with jeans and sneakers.

The collar buttons down to the shirt; no buttons means you're looking at a button up. A little extra trivia: An "Oxford" shirt, another colloquial throw-away term, doesn't refer to any old dress ...