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

widen \wid"en\, v. t. imp.  p. p. widened; p. pr.  vb. n.
   widening.
   to make wide or wider; to extend in breadth; to increase the
   width of; as, to widen a field; to widen a breach; to widen a
   stocking.
   1913 webster
see also:
widened widening 

[2] : WordNet (r) 2.0

widening
     n 1: an increase in width syn: broadening ant: narrowing
     2: a part of a road that has been widened to allow cars to pass
        or park syn: turnout
     3: the act of making something wider syn: broadening ant:
        narrowing
see also:
broadening narrowing turnout 

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

66 moby thesaurus words for "widening":
   access, accession, accretion, accrual, accruement, accumulation,
   addition, adjunct, advance, aggrandizement, ampliation,
   amplification, appreciation, ascent, augmentation, ballooning,
   bloating, boom, boost, broadening, buildup, crescendo, deployment,
   development, dispersion, edema, elevation, enlargement, expansion,
   extension, fanning out, flare, flood, gain, greatening, growth,
   gush, hike, hiking, increase, increment, inflation, jump, leap,
   magnification, mounting, multiplication, productiveness,
   proliferation, raise, raising, rise, snowballing, splay, spread,
   spreading, surge, swelling, tumescence, up, upping, upsurge,
   upswing, uptrend, upturn, waxing

Widening >> W Words
Widening, definition of term: Widening
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