How is &#39;adverse possession&#39; &#39;adverse&#39;?
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<p><a href="https://www.law.cornell.edu/wex/adverse_possession" rel="nofollow noreferrer">[ Source for English law : ]</a> Adverse Possession means someone occupying land belonging to someone else, without permission. If someone does this continuously for a number of years (normally 10 or 12 years) then, in certain circumstances, the land may become theirs.</p>
<p><a href="https://www.law.cornell.edu/wex/adverse_possession" rel="nofollow noreferrer">[ US Source : ]</a>
Adverse possession is a doctrine under which a person in possession of land owned by someone else may acquire valid title to it, so long as certain common law requirements are met, and the adverse possessor is in possession for a sufficient period of time, as defined by a statute of limitations.</p>
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<p>I already understand, and so ask not for, the definition. Instead: what motivated the use of <a href="http://www.etymonline.com/index.php?allowed_in_frame=0&amp;search=adverse" rel="nofollow noreferrer">adverse</a> to describe the legal notion? What semantic notions underlie the prosaic and the legal meanings?</p>

<p>The term originated in Anglo-Norman legal usage in the 14th C., and <em>advers</em> (that spelling) has the meaning "acting against or in opposition (to someone or something); opposing, antagonistic, actively hostile". It is often used in "adverse party" (and related spellings) meaning "the opposing party". The specific collocation "adverse possession" meaning "possession against (the interest of a person)" seems to be attested from 1776 in Contin. Comyn's Digest Laws Eng. "Twenty years adverse possession in defendant, takes away plantiff's right of possession".</p>

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