M-command
In generative grammar and related frameworks, m-command is a syntactic relation between two nodes in a syntactic tree. A node X {\displaystyle X} m-commands a node Y {\displaystyle Y} if the maximal projection of X {\displaystyle X} dominates Y {\displaystyle Y} , but neither X {\displaystyle X} nor Y {\displaystyle Y} dominates the other.