In a manner that alleviates, eases, or reduces the severity or intensity of something burdensome.
From alleviating (present participle) plus -ly (manner adverb). This creates an adverb describing how an action performs the function of relief.
The word 'alleviatingly' is technically correct but almost never used—it's the kind of word that exists in English grammar but not in English speech, like a ghost word haunting the dictionary.
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