In a manner lacking foundation, evidence, or justification; without any valid basis.
From baseless (base + -less, Old English suffix meaning without) + -ly (adverb-forming suffix). Baseless emerged in the 16th century to describe claims or accusations without support.
Accusing someone baselessly is worse than being wrong—you're not just mistaken, you're making claims with absolutely zero evidence to stand on, which makes it both dishonest and irresponsible.
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