The Collaborative International Dictionary of English v.0.48:

Punctuate \Punc"tu*ate\, v. t. [imp. & p. p. Punctuated; p.
   pr. & vb. n. Punctuating.] [Cf. F. ponctuer. See
   Punctual.]
   To mark with points; to separate into sentences, clauses,
   etc., by points or stops which mark the proper pauses in
   expressing the meaning.
   [1913 Webster]