# Definition:Metalanguage/Metasymbol

## Definition

A metasymbol is a symbol used in a metalanguage to represent an arbitrary collation in the object language.

Metasymbols are deliberately taken from a set of symbols that are not in the alphabet of the object language in question.

On $\mathsf{Pr} \infty \mathsf{fWiki}$, metasymbols are usually taken from any of:

uppercase letters: $P, Q, R, \ldots$ and subscripted versions: $P_1, P_2, \ldots$
the Greek alphabet: $\phi, \chi, \psi, \ldots$ and their subscripted versions: $\phi_1, \phi_2, \ldots$
uppercase bold: $\mathbf A, \mathbf B, \mathbf C, \ldots$ and their subscripted versions: $\mathbf A_1, \mathbf A_2, \ldots$

Which system is in use on a particular page depends to a certain extent on the nature of the source work which has inspired it.

## Also see

Altenative terms for a metasymbol are:

metalogical variable
metalogical symbol
metasyntactic variable[1].

## References

1. As immortalized by Terry Pratchett in Men at Arms: the dog Gaspode says, "Clothing has never been what you might call a thingy of dog wossname." Then he adds: "Two metasyntactic variables there. Sorry."