catchword vs guideword

catchword and guideword both are nouns.

Word	Noun	Adjective	Verb	Adverb
catchword	Yes	No	No	No
guideword	Yes	No	No	No

As nouns, catchword and guideword are synonyms defined as:

catchword and guideword: a word printed at the top of the page of a dictionary or other reference book to indicate the first or last item on that page

Other synonyms of catchword include guide word.

catchword (noun)	guideword (noun)
a favorite saying of a group, organization or individual	a word printed at the top of the page of a dictionary or other reference book to indicate the first or last item on that page
a word printed at the top of the page of a dictionary or other reference book to indicate the first or last item on that page