Definitions for "DOS prompt"
An indicator on the display that indicates that MS-DOS is ready to receive a command. The default prompt is the current drive letter followed by a greater-than sign (). C: is called 'C prompt', etc.
In DOS, it is usually the latest line of command when the computer is waiting for your input. It indicates which drive is in use, e.g. C:\ means the C drive is in use.
The visual indication from the MS-DOS command processor that the operating system is ready to accept a new command. The default DOS prompt is a path followed by a greater-than sign (for example, C:); the user can also design a custom prompt with the PROMPT command.