I think we also have a transatlantic difference. In my (UK) experience, odourous and malodourous is the norm, and odiferous is seen as an American usage. We see this as an exaggeration for effect like ‘splendiferous’, using the ‘ous’ suffix in a way like ‘sumptuous’.
From what I could discern about the history of Greek phonology, the sound of epsilon started as [e] in Ancient Greek, shifted to [ε] in Koine, and eventually shifted back to [e] for Modern Greek. Somehow we English speakers have picked up on the Koine [ε] pronunciation to the point that we use the epsilon glyph to represent the lax vowel sound (like in “fed”) instead of the tense vowel (as in “fate”).
Nope, ferriferous.
bob++, odoriferous, not odiferous.
Definition of odiferous in English:
ADJECTIVE
Variant spelling of odoriferous.
odoriferous is just a syllable too far.
That’s a funny definition, because odoriferous is closer to the original language. Doesn’t mean odiferous isn’t actually older, but it’s more derived.
Perhaps given some oomph by the Latin odium “hatred.”
Thereby changing the meaning altogether.
odiferous - hate-bearing
odoriferous - odor-bearing