n A part of any of several scientific instruments that moves back and forth to indicate a position
n (graphical user interface) A moving icon or other representation of the position of the pointing device.
n (graphical user interface) An indicator, often a blinking line or bar, indicating where the next insertion or other edit will take place. Also referred to as "the caret".
n (databases) A reference to a row of data in a table, which moves from row to row as data is retrieved by way of it.
n (programming) A design pattern in object oriented methodology in which a collection is iterated uniformly, also known as the iterator pattern.