Nefarious and preposterous.
Nefarious. Is that the same as infamous? Preposterous!
Infamous- adj. characterized by negative celebrity; having a reputation of the worst kind. From
in- which is not or negative, and
famous which is well-known. Antonym: illustrious. From Latin.
Infamy - n. evil reputation brought about by something criminal or shocking. (Latin)
Nefarious - adj. flagrantly wicked or impious. Synonym: vicious. From Latin.
Preposterous - adj. contrary to nature or reason, absurd.
So it is not preposterous to state that nefarious is synonymous with infamous, but it would not be accurate. Infamous means being famous for being nefarious. They are related, but not synonymous.
I do like that word, "illustrious." Yes. You may refer to me as the Illustrious Philolog.