head word is a noun meaning "a content word that can be qualified by a modifier". It carries 2 recorded senses.
a content word that can be qualified by a modifier
(grammar) the word in a grammatical constituent that plays the same grammatical role as the whole constituent
grammar
Definitions, synonyms and semantic relations for head word come from Princeton University’s WordNet. Commonness is measured against a corpus of everyday English. Full sources and licences.