fantasm vs apparition

fantasm and apparition both are nouns.

Word	Noun	Adjective	Verb	Adverb
fantasm	Yes	No	No	No
apparition	Yes	No	No	No

As nouns, fantasm and apparition are synonyms defined as:

Other synonyms of fantasm include phantasm, phantasma, phantom, shadow.

As nouns, fantasm and apparition are synonyms defined as:

Other synonyms of fantasm include phantasm, phantasma, phantom, specter, spectre.

fantasm (noun)	apparition (noun)
something existing in perception only	an act of appearing or becoming visible unexpectedly
a ghostly appearing figure	something existing in perception only
	the appearance of a ghostlike figure
	a ghostly appearing figure