ghost word vs word form

ghost word and word form both are nouns.

Word	Noun	Adjective	Verb	Adverb
ghost word	Yes	No	No	No
word form	Yes	No	No	No

As nouns, word form is a hypernym of ghost word; that is, word form is a word with a broader meaning than ghost word:

ghost word: a word form that has entered the language through the perpetuation of an error
word form: the phonological or orthographic sound or appearance of a word that can be used to describe or identify something

Other hypernyms of ghost word include descriptor, form, signifier.

ghost word (noun)	word form (noun)
a word form that has entered the language through the perpetuation of an error	the phonological or orthographic sound or appearance of a word that can be used to describe or identify something