Grammatical function (LFG)

In Lexical-Functional Grammar (Bresnan (ed.) 1982), the term grammatical function is used for grammatical relations.

Grammatical functions are subject of, object of, complement of, head of, etc., which in configurational languages correspond to specific syntactic positions.

Comments
Perhaps a slight difference between grammatical function and grammatical relation is that the former refers to one of the members of a relation, while the latter refers to a link between two elements.

Synonyms

 * grammatical relation
 * syntactic function

Link
Utrecht Lexicon of Linguistics