The Collaborative International Dictionary of English v.0.48:

Pertinent \Per"ti*nent\, a. [L. pertinens, -entis, p. pr. of
   pertinere: cf. F. pertinent. See Pertain.]
   1. Belonging or related to the subject or matter in hand; fit
      or appropriate in any way; adapted to the end proposed;
      apposite; material; relevant; as, pertinent illustrations
      or arguments; pertinent evidence.
      [1913 Webster]

   2. Regarding; concerning; belonging; pertaining. [R.]
      "Pertinent unto faith." --Hooker.
      [1913 Webster]

   Syn: Apposite; relevant; suitable; appropriate; fit.
        [1913 Webster] -- Per"ti*nent*ly, adv. --
        Per"ti*nent*ness, n.
        [1913 Webster]

WordNet (r) 3.0 (2006):

pertinently
    adv 1: in a pertinent way; "what is singular about his use of
           them is that no other artist, of his time or any other,
           has painted them so directly, intimately and pertinently"