The term "First World War" was already coined in September 1914 and again in 1918. When this was generally accepted is unknown, but likely sometime after US entry into WW2, mirroring the situation...
Hmm. Not sure what you are asking.
A plane is usually known by the manufacturer who built it. One name was a Sopwith. But there were many different models built by Sopwith. One was named "Camel"...