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Webster Dictionary (0.00 / 0 votes) Rate this definition: Amphi- a prefix in words of Greek origin, signifying both, of both kinds, on both sides, about, around
The word is possibly a portmanteau from Latin sylvestris and nympha, sylvestris being a common synonym for sylph in Paracelsus. Anthon and Trollope note a similar usage in the Aeneid, where silvestris is taken as an elliptical form of nympha silvestris (forest nymph).