half-truth

from WordNet (r) 3.0 (2006)

half-truth
    n 1: a partially true statement intended to deceive or mislead

from The Collaborative International Dictionary of English v.0.48

half-truth \half"-truth`\ (h[aum]f"tr[=oo]th), n.; pl.
   {half-truths} (h[aum]f"tr[=oo][th]z)`.
   a partially true statement, especially one intended to
   deceive or mislead.
   [WordNet 1.5]