This is the 8241st most frequent Russian word.
мамаевой
The word "мамаевой" is not standalone; it is a form of the feminine possessive adjective related to "мамаев," often meaning "Mamaev's" or "of Mamaev" when contextually linked to a name or thing.
Here, 'Мамаевой' is used as part of the possessive form 'Мамаевой кургана', indicating that these geographic features are related to the named entity 'Мамай' (Mamay).
Этот парк находится недалеко от Мамаевой кургана.
This park is located near the Mamayev Kurgan.
In this case, 'Мамаевой' modifies 'башне' (tower), referring to a structure associated with the historical figure Mamay or something named after him.
Разговоры о Мамаевой башне всегда интересны.
Talks about the Mamayev Tower are always interesting.
Here, 'Мамаевой' describes 'поляны' (meadow), creating a possessive or descriptive relationship.