This is the 3288th most frequent Russian word.
отделением
"Отделением" means "by/with the department," "branch," or "separation," depending on context.
The word 'отделением' is used here in the instrumental case to denote the entity that has been affected or involved in action.
После ремонта в больнице открыли новое отделение.
After the renovation, a new department was opened in the hospital.
In this sentence, 'отделением' refers to the process or action of separating, acting as a noun in instrumental case to explain the means by which the separation happens.
Сотрудники занимаются отделением бумаги от пластика для переработки.
Employees are separating paper from plastic for recycling.
In this example, 'отделением' is used in instrumental case to describe a characteristic of the building.