ditto mark vs ditto

ditto mark and ditto both are nouns.

Word	Noun	Adjective	Verb	Adverb
ditto mark	Yes	No	No	No
ditto	Yes	No	Yes	No

As nouns, ditto mark and ditto are synonyms defined as:

ditto mark and ditto: a mark used to indicate the word above it should be repeated

ditto mark (noun)	ditto (noun)
a mark used to indicate the word above it should be repeated	a mark used to indicate the word above it should be repeated

ditto mark (verb)	ditto (verb)
	repeat an action or statement