I don't know that you can make a statement one way or the other definitively. I have seen old British manuals refer to revolvers as pistols. So historically, especially in the early decades of the invention of the revolver, it continued to be called a pistol. But at some point in the 20th century, "gun people" (which includes military & LE) began calling semi-auto's and anything where the chamber is connected to the barrel a "Pistol" and revolvers were referred to as revolvers exclusively.
While it's technically not "incorrect", in modern parlance, a revolver shouldn't be referred to as a pistol.
