Tsarevich is the name of any son of the Tsar.
The heir is Tsesarevich.
Then Tsarevna is the name of any daughter of the Tsar.
Yes, in Russia the inheritance was by male side, BUT!
1. we had some Empress without their kings
during the 18-th century.
2. Last Tsar Nikolay Alexandrovich wanted to change the right of the inheritance in woman's sake, cause he had very weak son. So he decided to prepare his elder daughter Ol'ga to rule. So she could be Tsesarevna and then Tsaritsa.
-ovna/evna = paternal woman's name f.e. Ol'ga Nikolaevna.
The name "Tsarevna" in Russia was since old-old times, when they could marry only to royal person or had to go to the monastery.