The Collaborative International Dictionary of English v.0.48:

Adverse \Ad"verse\, a. [OE. advers, OF. avers, advers, fr. L.
   adversus, p. p. advertere to turn to. See Advert.]
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   1. Acting against, or in a contrary direction; opposed;
      contrary; opposite; conflicting; as, adverse winds; an
      adverse party; a spirit adverse to distinctions of caste.
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   2. Opposite. "Calpe's adverse height." --Byron.
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   3. In hostile opposition to; unfavorable; unpropitious;
      contrary to one's wishes; unfortunate; calamitous;
      afflictive; hurtful; as, adverse fates, adverse
      circumstances, things adverse.
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            Happy were it for us all if we bore prosperity as
            well and wisely as we endure an adverse fortune.
                                                  --Southey.
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   Adverse possession (Law), a possession of real property
      avowedly contrary to some claim of title in another
      person. --Abbott.
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   Syn: Averse; reluctant; unwilling. See Averse.
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