[1] : The Collaborative International Dictionary of English v.0.48

principally \prin"cipally\, adv.
   in a principal manner; primarily; above all; chiefly; mainly.
   1913 webster

[2] : WordNet (r) 2.0

principally
     adv : for the most part; "he is mainly interested in butterflies"
           syn: chiefly, primarily, mainly, in the main
see also:
chiefly primarily mainly in the main 

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

18 moby thesaurus words for "principally":
   above all, at bottom, basically, chiefly, especially, essentially,
   first and foremost, fundamentally, in essence, in the main,
   largely, mainly, mostly, on the whole, overall, particularly,
   predominantly, primarily

Principally >> P Words
Principally, definition of term: Principally
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