Experts are not certain, but it is probably from an Ancient Greek word which means something like "one of the two". I.e., it was probably a name originally given to one of twins.
Ekaterina Krupenina's birth name is Ekaterina Aleksandrovna Krupenina.
Ekaterina Li's birth name is Ekaterina Valerevna Li.
Ekaterina Shapkayts's birth name is Ekaterina Yurevna Shapkayts.
Ekaterina Ryndyk's birth name is Ekaterina Yurevna Ryndyk.
Ekaterina Shcheglova's birth name is Ekaterina Nikolaevna Shcheglova.
Ekaterina Kabak's birth name is Ekaterina Borisovna Kabak.
Ekaterina Chtchelkanova's birth name is Ekaterina Nikolaievna Chtchelkanova.
Ekaterina Botziou's birth name is Ekaterina Maria Botziou.
Ekaterina Yudina's birth name is Ekaterina Sergeevna Yudina.
Ekaterina Grokhovskaya's birth name is Ekaterina Aleksandrovna Grokhovskaya.
Ekaterina Gordeeva's birth name is Ekaterina Alexandrovna Gordeeva.
Ekaterina Vilkova's birth name is Ekaterina Nikolaevna Vilkova.