In an exaggerative manner; in a way that tends toward or is characterized by exaggeration.
From exaggerative (the adjective) plus -ly (adverb suffix). This double-suffix construction (base + -ive + -ly) is common in English for creating manner adverbs.
Adding both -ive and -ly to a root word creates an adverb that's even more formal—it's the kind of word you'd find in academic writing when someone wants to describe behavior in clinical precision.
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