reg·is·ter 
(rĕjĭ-stər)
(rĕjĭ-stər)n.
1.
a. A formal or official recording of items, names, or actions.
b. A book for such entries.
c. An entry in such a record.
2. The act of registering.
3. A device that automatically records a quantity or number.
4. Computers A part of the central processing unit used as a storage location.
5. An adjustable, grill-like device through which heated or cooled air is released into a room.
6. A state of proper alignment: to be in register.
7. Printing
a. Exact alignment of the lines and margins on the opposite sides of a leaf.
b. Proper positioning of colors in color printing.
8. Music
a. The range of an instrument or a voice.
b. A part of such a range.
c. A group of matched organ pipes; a stop.
9. A variety or level of language used in a specific social setting: speaking in an informal register; writing in a scientific register.
v. reg·is·tered, reg·is·ter·ing, reg·is·ters
v.tr.
1.
a. To enter in an official register.
b. To enroll officially or formally, especially in order to vote or attend classes.
2.
a. To set down in writing: registered the events of the day in his diary.
b. To express or make known: registered his dissatisfaction with the chef.
3.
a. To indicate (data). Used of an instrument or scale.
b. To be indicated as: The earthquake registered 6.8 on the Richter scale.
4. To give outward signs of; express: Her face registered surprise.
5. To attain or achieve: registered a new high in sales.
6. To cause (mail) to be officially recorded and specially handled by payment of a fee.
7. To adjust so as to be properly aligned.
v.intr.
1. To place or cause placement of one's name in a register.
2. To have one's name officially placed on a list of eligible voters.
3. To enroll as a student.
4. To have a list of gifts for preferred wedding presents, as at a store. Used of a couple.
5. To be indicated on an instrument or a scale.
6. To be shown or expressed, as on the face: The teacher's reprimand did not register on the students' faces.
7. To make an impression; be recorded in the mind: The warning failed to register.
8. To be in proper alignment.
[Middle English registre, from Old French, from Medieval Latin registrum, alteration of Late Latin regesta, from Latin, neuter pl. past participle of regerere, to record : re-, re- + gerere, to carry.]
regis·ter·er n.
regis·tra·ble (-ĭ-strə-bəl) adj.