tam-o'-shanter vs tammy

tam-o'-shanter and tammy both are nouns.

Word	Noun	Adjective	Verb	Adverb
tam-o'-shanter	Yes	No	No	No
tammy	Yes	No	No	No

As nouns, tam-o'-shanter and tammy are synonyms defined as:

Other synonyms of tam-o'-shanter include tam.

tam-o'-shanter (noun)	tammy (noun)
a woolen cap of Scottish origin	plain-woven (often glazed) fabric of wool or wool and cotton used especially formerly for linings and garments and curtains
	a woolen cap of Scottish origin