Leicester vs Leicestershire

Leicester and Leicestershire both are nouns.

Word	Noun	Adjective	Verb	Adverb
Leicester	Yes	No	No	No
Leicestershire	Yes	No	No	No

As nouns, Leicester and Leicestershire are synonyms defined as:

Leicester and Leicestershire: a largely agricultural county in central England

Leicester (noun)	Leicestershire (noun)
an industrial city in Leicestershire in central England; built on the site of a Roman settlement	a largely agricultural county in central England
a largely agricultural county in central England