any of various large tropical carnivorous lizards of Africa and Asia and Australia; fabled to warn of crocodiles | equipment that involves the controlled conduction of electrons (especially in a gas or vacuum or semiconductor) |
a piece of electronic equipment that keeps track of the operation of a system continuously and warns of trouble | |
electronic equipment that is used to check the quality or content of electronic transmissions | |
display produced by a device that takes signals and displays them on a television screen or a computer monitor | |
someone who gives a warning so that a mistake can be avoided | |
someone who supervises (an examination) | |