This is the 5823rd most frequent Russian word.
развлекательной
Entertaining.
Here, "развлекательной" is used as an adjective describing the industry linked to providing entertainment.
Моя сестра работает в развлекательной индустрии.
My sister works in the entertainment industry.
In this sentence, "развлекательной" describes a specific area designed for recreation and leisure activities.
Мы провели вечер в развлекательной зоне парка.
We spent the evening in the recreational park area.
The word "развлекательной" contrasts entertainment-focused content with the academic nature of the book.