metacommand

A metacommand is a command that operates on the command interpreter or the environment in which commands are executed, rather than performing a domain task directly. It is a higher-level instruction that governs how other commands behave, how they are discovered, defined, or executed, and how the session is configured. Metacommands are found in many interactive systems, including shells, editors, database CLIs, and data-analysis REPLs. They enable users to tailor the command environment, extend the command set, or switch between operation modes.

Typically a metacommand provides options to configure options, define new commands or aliases, or enter a special mode such as macro recording, batch processing, or verbose logging. They usually have distinct syntax or a reserved namespace to separate them from ordinary commands, and their effects persist according to session scope or can be saved to a profile.

Metacommands are different from the tasks the system performs for the user; macros, scripts, or workflows are built from ordinary commands, while metacommands manage the environment itself. However, some systems use the term loosely, and the line between metacommands and advanced scripting can blur.

Examples across environments include commands to set interpreter options, define aliases or new commands, switch input modes, or enable meta-features like scripting or macro recording. Because they control how commands are interpreted, metacommands raise considerations around discoverability, security, and portability within different implementations.