main entry word vs signifier

main entry word and signifier both are nouns.

Word	Noun	Adjective	Verb	Adverb
main entry word	Yes	No	No	No
signifier	Yes	No	No	No

As nouns, signifier is a hypernym of main entry word; that is, signifier is a word with a broader meaning than main entry word:

main entry word: the form of a word that heads a lexical entry and is alphabetized in a dictionary
signifier: the phonological or orthographic sound or appearance of a word that can be used to describe or identify something

Other hypernyms of main entry word include descriptor, form, word form.

main entry word (noun)	signifier (noun)
the form of a word that heads a lexical entry and is alphabetized in a dictionary	the phonological or orthographic sound or appearance of a word that can be used to describe or identify something