By one's own admission; confessing or acknowledging something that might be surprising or contrary to expectations.
From 'admitted' (past tense of 'admit'), from Latin 'admittere' (to allow entrance, acknowledge), with the adverbial suffix '-ly' added. The word emerged in English usage in the 18th century.
When we say 'admittedly,' we're essentially signaling to a listener that we're about to concede a point against ourselves—it's a verbal way of lowering our guard and being honest.
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