The general opposite of the noun "land" is "sea." These are the two types of surface. Historically the opposite of travel by land was by sea, but this could now apply to travel by "ground" as opposed to by "air."
If you are referring to what an aircraft does, then 'take off' would be a suitable opposite. For sea travel the opposite could be to "set sail."
If you refer to what you do to a fish after hooking it, then the opposite might be 'lose' but it is not so clear.
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It really depends upon which meaning of 'land' you mean and exactly what you mean by 'opposite'. When people refer to the 'opposite' of a word they normally mean its antonym and this would typically only apply to adjectives and adverbs, and certain verbs that have a clear antonym, and to nouns based on them.
Well, the opposite of "Wonder" is "Dread" and the Opposite of "Land" is "sea". So, my answer would be Dreadsea?
This is an alternative spelling of demesne which means an area of land and as such can have no opposite.
The opposite land use would likely be a factory, or (ironically) a parking lot.
Pastoral Land
Blithe means cheerful, gay: its opposite could be morose, depressed Blithe basically means oblivion. You are perfectly confident in lala land. The opposite would be 'concerned' or 'circumspect'.
land lady landlady
It has to land in the opposite diagonal service box (because you face the opposite diagonal service box when you are serving).
No-man's-land.
Well, the opposite of "Wonder" is "Dread" and the Opposite of "Land" is "sea". So, my answer would be Dreadsea?
This is an alternative spelling of demesne which means an area of land and as such can have no opposite.
It could be tenant or renter if the person that rents from a landlady is lessee or tenant, land lord if only the gender is meant by opposite, or homelsss person if the opposite means the person without a rental property.
Fallow land means land that has not been cultivated and seeded. The soil can be fertile, just nothing is being grown on it. Cultivated land that actively has plants growing on it is the opposite of fallow
opposite front side
Dry land.
the groove
Antonym means opposite, so I guess the opposite of "sea" would be "land".
The opposite land use would likely be a factory, or (ironically) a parking lot.