1. A written book or system of public records and information: The election register, or record, was kept in a locked safe when the office was closed.
2. The vocal range of a singer’s voice or that of an instrument: The register of the piano is more than seven octaves.

1. To sign up formally for or to enroll for something: When Manfred stayed at the hotel, he had to register at the front desk before he could get a key to the room.

Christine plans to register for three lecture courses this summer.

2. To suggest or to convey an impression: Ronda Smith's name did not at first register with Karl and he was embarrassed when he realized that she was one of his former teachers.

Mike's drama teacher taught him how to register "surprise" in his face.

An official of an institution (educational, medical, corporate, etc.) who is responsible for maintaining records, processing paper work for admissions, etc.: The registrar at the front desk knew the answer to Mabel's question regarding whether her application for admittance to the college had been accepted.

The office of the registrar was located in the same building as the president of the university.