sissy vs cissy

sissy is a noun but cissy is not a noun.

Word	Noun	Adjective	Verb	Adverb
sissy	Yes	Yes	No	No
cissy	No	Yes	No	No

As adjectives, sissy and cissy are synonyms defined as:

Other synonyms of sissy include effeminate, emasculate, epicene, sissified, sissyish.

sissy (noun)	cissy (noun)
a timid man or boy considered childish or unassertive

sissy (adjective)	cissy (adjective)
having unsuitable feminine qualities	having unsuitable feminine qualities