This is the 7618th most frequent Russian word.
елку
"Елку" means "Christmas tree" or "fir tree" in the accusative case in Russian.
'ёлку' refers to the Christmas tree being decorated, used in the accusative case as the direct object of the verb.
Я наряжаю ёлку к Новому году.
I am decorating the Christmas tree for New Year.
'ёлку' refers to a fir tree to be obtained, used in the accusative case because of motion toward obtaining the object.
Мы пошли в лес за ёлку.
We went to the forest to get a fir tree.
'ёлку' refers to the tree being circled around, used in the accusative case as the object of the preposition.