M-command

In theoretical linguistics, m-command is a syntactic relation between two elements in a tree structure. It is a broader version of c-command. Aoun and Sportiche's (1983) definition of c-command in fact corresponds to what is now known as "m-command".

Chomsky (1986) established the standard definition of m-command. If "X" and "Y" are two nodes in a syntactic tree, "X" m-commands "Y" if and only if:
* "X" does not dominate "Y",
* "Y" does not dominate "X", and
* the maximal projection of "X" dominates "Y".

The notion of maximal projection is adopted from X-bar theory.

The difference between c-command and m-command is that "X" m-commands everything that it c-commands, and in addition it m-commands the element in the specifier position of the phrase that it heads.

M-command is used in the formulation of the syntactic relation government.

References

*Cite journal| last=Aoun |first=Joseph |coauthors=Dominique Sportiche| year=1983| title=On the Formal Theory of Government |journal=Linguistic Review |volume=2|pages=211–236
*Cite book | last=Chomsky |first=Noam |authorlink=Noam Chomsky |year=1986 | title=Barriers |location=Cambridge, MA |publisher=MIT Press