What does amphibious mean?
The definition of amphibious
Am*phib”i*ous, a.
Etym: [Gr. i. e., both on land in water;

1 Having the ability to live both on land and in water, as frogs, crocodiles, beavers, and some plants.
2 Pertaining to, adapted for, or connected with, both land and water. The amphibious character of the Greeks was already determined: they were to be lords of land and sea. Hare.
3 Of a mixed nature; partaking of two natures. Not in free and common socage, but in this amphibious subordinate class of villein socage. Blackstone.