superstition vs superstitious notion

superstition and superstitious notion both are nouns.

Word	Noun	Adjective	Verb	Adverb
superstition	Yes	No	No	No
superstitious notion	Yes	No	No	No

As nouns, superstition and superstitious notion are synonyms defined as:

superstition and superstitious notion: an irrational belief arising from ignorance or fear

superstition (noun)	superstitious notion (noun)
an irrational belief arising from ignorance or fear	an irrational belief arising from ignorance or fear