In a manner that improves or makes something better; in an ameliorative way.
From 'ameliorative' plus the adverb suffix '-ly'. This creates the adverbial form describing how an action or condition functions to improve things.
This is a rare word you might encounter in academic writing—imagine a sentence like 'The new policy worked amelioratively to reduce poverty.' It's precise but formal, which is why most writers prefer 'in an improving manner' in everyday speech.
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