This is the 10254th most frequent Russian word.
богослужения
Religious services or worship.
The word "богослужения" is used here in its plural form to denote religious services generally.
Каждую неделю мы ходим на богослужения в церковь.
Every week, we go to church services.
In this case, "богослужения" is used in the singular genitive case to indicate being during the service.
Вчера во время богослужения священник рассказал поучительную историю.
Yesterday, during the service, the priest shared an educational story.
Here, "богослужения" is in the accusative case plural and signifies that services are a part of the event's schedule.