from The Century Dictionary.
- In Roman antiquity, a festival of which the object was to invoke the favor of the gods toward the fertility of the fields.
Sorry, no etymologies found.
And except in the country districts these ceremonies were more and more absorbed, as time went on, into the social, military, and political life of the community, as _e. g._ the lustration of the host became a political census; or they tended to disappear altogether, like the _ambarvalia_ and perhaps the _amburbium_.
_ambarvalia_, must mean a rite of this processional kind.