Bly Is A Boys Name With Norse, Irish, And English Roots. Meaning "descendant Of Blighe," Bly Is A Modern Reinvention Of The Irish Surname Ó Blighe, Which In Turn Derived From The Norse Name Bligr. Calling To Mind Viking Explorers And Celtic Rulers, Bly Is A Stand-out Choice For Your Little Warrior. Add The English Translation Of "carefree" To The Mix, And Baby Bly Can Take On Anything That Comes Their Way.