It's usually a bottle with a stopper closure. Stopper as in a glorified plug, as in glass usually. That's just usually. I'm sure a bottle with a screw top cap has been called a flacon by some producer down the line. Also, it can be a small bottle. Pure perfume often comes in small flacons.
About the Creed flacons, they're certainly big bottles. They don't have sprays, they're so big they're meant to be poured into a re-fillable Creed atomizer from which you spray onto yourself. Those atomizers are expensive, about US$100, but you can go cheap and find an ounce or two ounce size (or other size) atomizer elsewhere. I don't know where though, and they're usually cheap.
Hope this helps,