Source : Webster's Revised Unabridged Dictionary (1913)

Continuously \Con*tin"u*ous*ly\, adv.
   In a continuous maner; without interruption. --
   {Con*tin"u*ous*ness}, n.

Source : WordNet®

continuousness
     n : the quality of something that continues without end or
         interruption [syn: {ceaselessness}, {incessancy}, {incessantness}]