Admittedly; in a way that is openly or avowedly stated.
Declared (adjective, from declare + -ed) + -ly adverbial suffix. Literally means 'in a declared manner.'
This adverb is almost extinct in modern English—people say 'admittedly' or 'openly' instead—but you'll find it in older literature like 19th-century novels where it conveyed a wry acknowledgment of something awkward or inconvenient.
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