phantasm vs illusion

phantasm and illusion both are nouns.

Word	Noun	Adjective	Verb	Adverb
phantasm	Yes	No	No	No
illusion	Yes	No	No	No

As nouns, illusion is a hypernym of phantasm; that is, illusion is a word with a broader meaning than phantasm:

Other hypernyms of phantasm include semblance.

phantasm (noun)	illusion (noun)
something existing in perception only	the act of deluding; deception by creating illusory ideas
a ghostly appearing figure	an illusory feat; considered magical by naive observers
	something many people believe that is false
	an erroneous mental representation