The Collaborative International Dictionary of English v.0.48:

Connate \Con"nate\ (?; 277), a. [L. connatus; con- + natus born,
   p. p. of nasci. See Cognate.]
   [1913 Webster]
   1. Born with another; being of the same birth.
      [1913 Webster]

   2. Congenital; existing from birth. "Connate notions."
      --South.
      [1913 Webster]

            A difference has been made by some; those diseases
            or conditions which are dependent on original
            conformation being called congenital; while the
            diseases of affections that may have supervened
            during gestation or delivery are called connate.
                                                  --Dunglison.
      [1913 Webster]

   3. (Bot.) Congenitally united; growing from one base, or
      united at their bases; united into one body; as, connate
      leaves or athers. See Illust. of Connate-perfoliate.
      [1913 Webster]

WordNet (r) 3.0 (2006):

connate
    adj 1: of similar parts or organs; closely joined or united; "a
           connate tomato flower" [ant: adnate]
    2: related in nature; "connate qualities" [syn: connate,
       cognate]

Moby Thesaurus II by Grady Ward, 1.0:

54 Moby Thesaurus words for "connate":
   affiliated, affinal, affinitive, agnate, akin, allied, atavistic,
   bodily, born, coeval, cognate, congeneric, congenerous, congenial,
   congenital, connatal, connatural, connected, consanguine,
   conspecific, constitutional, correlative, deep-seated, elemental,
   enate, essential, genetic, genetically related, hereditary,
   in the blood, inborn, inbred, incarnate, incident, indigenous,
   indwelling, inherited, innate, instinctive, instinctual, intrinsic,
   kindred, native, native to, natural, natural to, of common source,
   organic, physical, primal, related, related by blood,
   temperamental, unacquired