Definition of "multi-word"

The single-word/multi-word distinction involves what is most plausibly a difference in terminal elements among items of the same category type (e.g. adjective phrases).

2004, John A. Hawkins, Efficiency and Complexity in Grammars‎

The verb categories included two-word multi-word verbs, though terms of more than two words were placed in the phrase category.

2012, James Lambert, “Beyond Hobson-Jobson: A new lexicography for Indian English”, in World Englishes‎, page 297