cittern vs cithern

cittern and cithern both are nouns.

Word	Noun	Adjective	Verb	Adverb
cittern	Yes	No	No	No
cithern	Yes	No	No	No

As nouns, cittern and cithern are synonyms defined as:

cittern and cithern: a 16th century musical instrument resembling a guitar with a pear-shaped soundbox and wire strings

Other synonyms of cittern include cither, citole, gittern.

cittern (noun)	cithern (noun)
a 16th century musical instrument resembling a guitar with a pear-shaped soundbox and wire strings	a 16th century musical instrument resembling a guitar with a pear-shaped soundbox and wire strings