what is "on the floor"?

[coach/ref]

Before we boot out the phrase "on the floor" we must consider how effective and concise it is. Every one of us knows what it means, and 90% of coaches know what it means, so why not adopt it? When a ref says, "on the floor" all of the players know immediately that they do not need to line up for shots, so they are not standing around confused and the game continues at a good pace.

Also, see rule 4-45 article 1 for use of the term "floor."