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

pioneer \pi`oneer"\, v. t.  i. imp.  p. p. pioneered; p.
   pr.  vb. n. pioneering.
   1. to go before, and prepare or open a way for; to act as
      pioneer.
      1913 webster

   2. to take part in the early development of; to break ground
      in; to invent or originate.
      pjc
see also:
pioneered pioneering 

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

pioneering \pi`oneer"ing\, a.
   groundbreaking; originating; -- of efforts that begin work in
   a field or on a topic not previously widely known.
   pjc

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