I encountered this while reading Astérix. The exchange goes as follows:
(Astérix and Obélix are walking down a newly-constructed Roman road out of Lutèce)
Astérix: Quelle circulation !
Obélix: Les jours de beau temps, il doit y avoir des amphorisages !
This word doesn't come up in any dictionaries nor in google image search, so I assume it's some sort of joke or play on words. What might it mean?