Enrollment (American spelling) or enrolment (British spelling) may refer to: Matriculation, the process of initiating attendance to a school The act of entering an item into a roll or scroll. The total number of students properly registered and/or attending classes at a school (see List of largest universities by enrollment) Concurrent enrollment, the process in which high school students enrol at a university or college usually to attain college credit The participation of human subjects in a clinical trial Biometrics, the process of adding a user's credentials to the authentication system. The process of being entered onto an electoral roll Membership in a federally recognized American Indian tribe The defensive curling of a trilobite over its soft ventral organs. Volvation, the defensive curling of other arthropods such as pill bugs rolling themselves into a "pill". Enrollment may also refer to: Enrolled bill, a legislative bill in the United States that has been enacted by a legislature See also Roll (disambiguation)