Headword
WordNet
noun
(1) A word placed at the beginning of a line or paragraph (as in a dictionary entry)
(2) A word that is qualified by a modifier
WiktionaryText
Noun
- a word used as the title of a section, particularly in a dictionary, encyclopedia, or thesaurus
- any word which may be modified by an adjunct
- a very discerning car shopper, "shopper" is the headword.