tammy vs tam-o'-shanter

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

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

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

Other synonyms of tammy include tam.

tammy (noun)	tam-o'-shanter (noun)
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
a woolen cap of Scottish origin