manganese vs Mn

manganese and Mn both are nouns.

Word	Noun	Adjective	Verb	Adverb
manganese	Yes	No	No	No
Mn	Yes	No	No	No

As nouns, manganese and Mn are synonyms defined as:

manganese and Mn: a hard brittle grey polyvalent metallic element that resembles iron but is not magnetic; used in making steel; occurs in many minerals

Other synonyms of manganese include atomic number 25.

manganese (noun)	Mn (noun)
a hard brittle grey polyvalent metallic element that resembles iron but is not magnetic; used in making steel; occurs in many minerals	a hard brittle grey polyvalent metallic element that resembles iron but is not magnetic; used in making steel; occurs in many minerals