In a manner showing smug satisfaction and lack of awareness about problems or dangers; with self-satisfied unconcern.
From complacent (the -cy variant's adjective form) + -ly. 'Complacently' is the standard modern adverbial form, while 'complacentially' remains an obsolete alternative.
The adverb 'complacently' has become standard enough that it appears in regular speech and writing about politics, business, and social issues—people have recently rediscovered this word to describe institutional and governmental attitudes toward emerging crises, making it newly relevant to contemporary discourse.
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