The Czarina means the wife of a Russian tsar or Russian empress. It is often spelt as tsaritsa, czaritza, tsarina and tsaritsa. It can also be used to state a level of a performer such as the "Czarina of Dance."
The Czarina Waltz as a music goes back to the 1880's however Anna Pavlova (1881-1931) and Max Rabinoff are said to have created and danced the Czarina Waltz as a social dance around 1915, so maybe theirs was an official version thru choreography to said song or maybe that it was dedicated to Feodorowna 'the Czarina of Russia' which became popular do to Pavlova's popularity as a dancer at the time or maybe it was dedicated to Pavlova as the 'Czarina of dance', sorry but at the moment it is not clear. There were lessor known Czarina named dances such as Polkas, Mazurkas, Schottische etc. as well as even older 'Czar' named dances such as the Czar Polka etc.
There was a dancer called Czarina "The Clever Toe Dancer" who was popular around the 1900's. There is no known footage of Pavlova doing this waltz, but I put together a short clip of her social dancing a waltz to waltz music.