The term "middle level" can refer to a variety of things depending on the context in which it is used. Generally, however, it refers to something that falls between two extremes or categories - either above or below what would be considered average or typical.
In some cases, middle level may describe a specific age group or developmental stage. For example, "middle school" is the term commonly used in the United States for the grades between elementary and high school, typically encompassing students aged around 10-14 years old. In this context, "middle level" would refer to a period of transition and growth as children move from childhood into adolescence.
In other instances, middle level may be used in reference to something that is neither particularly high nor low in quality or value. For example, if someone were to say they had a "middle-level job," it would imply that the position was not exceptional but also did not fall below average standards.
Overall, the term "middle level" can be used to describe something that falls between two extremes and is typically neither particularly high nor low in quality or value.