Antonyms of adj overland

1 sense of overland

Sense 1
overland -- (traveling or passing over land; "an overland journey"; "the overland route used by Marco Polo")

INDIRECT (VIA aquatic, terrestrial) -> amphibious -- (operating or living on land and in water; "amphibious vehicles"; "amphibious operations"; "amphibious troops"; "frogs are amphibious animals")
INDIRECT (VIA terrestrial, amphibious) -> aquatic -- (operating or living or growing in water; "boats are aquatic vehicles"; "water lilies are aquatic plants"; "fish are aquatic animals")

Similarity of adj overland

1 sense of overland

Sense 1
overland -- (traveling or passing over land; "an overland journey"; "the overland route used by Marco Polo")
       => terrestrial (vs. amphibious) (vs. aquatic) -- (operating or living or growing on land)