[1] : WordNet (r) 2.0

effortlessly
     adv : without effort or apparent effort; "she danced gracefully
           and effortlessly"; "swallows gliding effortlessly
           through the air"

[2] : Moby Thesaurus II by Grady Ward, 1.0

21 moby thesaurus words for "effortlessly":
   adeptly, adroitly, easily, efficiently, expertly, facilely, freely,
   hands down, lightly, like clockwork, like nothing, no sweat,
   on easy terms, proficiently, readily, simply, skillfully, smoothly,
   swimmingly, well, without difficulty

Effortlessly >> E Words
Effortlessly, definition of term: Effortlessly
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