Isn't "space copter" a bit of a misnomer? Isn't a copter a device with whirring blades tilted just so to cause thrust through a fluid medium (to wit, a propelle

Isn't "space copter" a bit of a misnomer? Isn't a copter a device with whirring blades tilted just so to cause thrust through a fluid medium (to wit, a propeller)? And isn't space defined often as that place where there is no such fluid like medium? So wouldn't it make more sense for it to be called a "Mars Copter"?