In an artificial, unnatural, or pretended manner; with deliberate affectation.
From 'affected' (influenced; or artificially pretended) + '-ly' (adverb suffix). 'Affected' comes from Latin 'affectus' (influenced or pretended). The '-ly' transforms the adjective into describing how an action is performed.
You can say someone 'affected' an accent, but when they do it 'affectedly,' you're describing the actual performance—the exaggerated, clearly-fake way they're doing it. It's a word for calling out phoniness!
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