decalcomania vs decal

decalcomania and decal both are nouns.

Word	Noun	Adjective	Verb	Adverb
decalcomania	Yes	No	No	No
decal	Yes	No	No	No

As nouns, decalcomania and decal are synonyms defined as:

decalcomania and decal: either a design that is fixed to some surface or a paper bearing the design which is to be transferred to the surface

decalcomania (noun)	decal (noun)
the art of transferring designs from specially prepared paper to a wood or glass or metal surface	either a design that is fixed to some surface or a paper bearing the design which is to be transferred to the surface
either a design that is fixed to some surface or a paper bearing the design which is to be transferred to the surface