The Collaborative International Dictionary of English v.0.48:

Impinge \Im*pinge"\, v. t. [imp. & p. p. Impinged; p. pr. &
   vb. n. Impinging.] [L. impingere; pref. im- in + pangere to
   fix, strike; prob. akin to pacisci to agree, contract. See
   Pact, and cf. Impact.]
   To fall or dash against; to touch upon; to strike; to hit; to
   clash with; -- with on or upon.
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         The cause of reflection is not the impinging of light
         on the solid or impervious parts of bodies. --Sir I.
                                                  Newton.
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         But, in the present order of things, not to be employed
         without impinging on God's justice.      --Bp.
                                                  Warburton.
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