preconceived idea vs parti pris

preconceived idea and parti pris both are nouns.

Word	Noun	Adjective	Verb	Adverb
preconceived idea	Yes	No	No	No
parti pris	Yes	No	No	No

As nouns, preconceived idea and parti pris are synonyms defined as:

preconceived idea and parti pris: an opinion formed beforehand without adequate evidence

Other synonyms of preconceived idea include preconceived notion, preconceived opinion, preconception, prepossession.

preconceived idea (noun)	parti pris (noun)
an opinion formed beforehand without adequate evidence	an opinion formed beforehand without adequate evidence