Source : Webster's Revised Unabridged Dictionary (1913)

Foist \Foist\, v. t. [imp. & p. p. {Foisted}; p. pr. & vb. n.
   {Foisting}.] [Cf. OD. vysten to fizzle, D. veesten, E. fizz,
   fitchet, bullfist.]
   To insert surreptitiously, wrongfully, or without warrant; to
   interpolate; to pass off (something spurious or counterfeit)
   as genuine, true, or worthy; -- usually followed by in.

         Lest negligence or partiality might admit or foist in
         abuses and corruption.                   --R. Carew.

         When a scripture has been corrupted . . . by a
         supposititious foisting of some words in. --South.