publicly (adv.)youdaoicibaDictYouDict[publicly 词源字典]
1560s, "in public," from public (adj.) + -ly (2). From 1580s as "by the public." Variant publically is attested from 1812, perhaps based on the fact that publicly is the only exception in this class of words, which as a rule are spelled -ically though often they are pronounced otherwise.[publicly etymology, publicly origin, 英语词源]