In a manner that is stubbornly opposite to what is expected; in a contrary or contradictory way.
From 'contrarious' (opposite) plus the adverbial suffix '-ly'. A rare adverbial form emphasizing obstinate opposition or contradictory behavior.
This word is so uncommon that most dictionaries don't list it, but it appears in historical texts—language evolved to favor the simpler 'contrarily' instead.
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