The Collaborative International Dictionary of English v.0.48:

Pectinate \Pec"ti*na`te\, Pectinated \Pec"ti*na`ted\, a. [L.
   pectinatus, p. pr. of pectinare to comb, from pecten, -inis,
   a comb; cf. Gr. pe`kein to comb, AS. feax hair, OHG. fahs, E.
   paxwax.]
   1. Resembling the teeth of a comb.
      [1913 Webster]

   2. (Nat. Hist.) Having very narrow, close divisions, in
      arrangement and regularity resembling those of a comb;
      comblike; as, a pectinate leaf; pectinated muscles. See
      Illust.
      (e) of Antenn[ae].
          [1913 Webster]

   3. Interlaced, like two combs. [R.] "Our fingers pectinated,
      or shut together." --Sir T. Browne.
      [1913 Webster]

   Pectinate claw (Zool.), a claw having a serrate edge, found
      in some birds, and supposed to be used in cleaning the
      feathers.
      [1913 Webster]

WordNet (r) 3.0 (2006):

pectinate
    adj 1: like a comb