This is the 8580th most frequent Russian word.
одессой
"Одессой" is the instrumental case of "Одесса," meaning "by/with Odessa," referring to the city Odessa in Ukraine.
Here, 'Одессой' is used in the instrumental case, expressing the means by which admiration is directed.
Я восхищаюсь Одессой за её богатую культуру.
I admire Odessa for its rich culture.
In this sentence, 'Одессой' is again in the instrumental case, indicating accompaniment or association during the travel.
Летом мы путешествовали с Одессой и её друзьями.
In summer, we traveled with Odessa and her friends.
Here, 'Одессой' is part of a prepositional case construction highlighting the subject of the story, and 'об Одессой' specifically means 'about Odessa' in Russian.