adverb Date: 1611 in an important way , it is important that , Usage: A number of commentators have objected to ~ as a sentence modifier (sense 2) and have recommended important instead. Actually both the adverb and the adjective are in reputable standard use in this function. Important is always used with more or most . Importantly is somewhat more flexible in not requiring more or most .
IMPORTANTLY
Meaning of IMPORTANTLY in English
Merriam Webster. Explanatory English dictionary Merriam Webster. Толковый словарь английского языка Мерриам-Уэбстер. 2012