Senior is a term used in the United States to describe a student in the 4th year of study (generally referring to high school or college/university study).
In the United States, the 12th grade is usually the fourth and final year of a student's high school period and is referred to as senior year. In England and Wales, students in their tenth year and above in Secondary School are seniors; in Scotland, students in their fifth year and above are seniors. In the Canadian province of Ontario, high school students in their third year and above are considered to be seniors.
In the United States, the final year of a student's education towards a bachelor's degree, typically the fourth year, is known as the senior year.
In college athletics, a student in their final year of eligibility is known as a senior.
The term super senior is used in the United States to refer to a fifth-year student who has not completed the graduation requirements by the end of the fourth year, and thus is required to stay an additional year to complete said requirements.