doubtlessly

adv

1. (proscribed, sometimes)Without question; indubitably.

   “There are doubtlessly more insects than mammals.”

2. (obsolete)Without feeling doubt, without misgivings.

   “Some powers diuine, or els infernall, mixt Their angry ſeedes at his conception: For he was neuer ſprong of humaine race, Since with the ſpirit of his fearefull pride, He dares so doubtleſly reſolue of rule.”