cousin \cous"in\ ku^z"'n, n. f. cousin, ll. cosinus,
   cusinus, contr. from l. consobrinus the child of a mother's
   sister, cousin; con- + sobrinus a cousin by the mother's
   side, a form derived fr. soror for sosor sister. see
   sister, and cf. cozen, coz.
   1. one collaterally related more remotely than a brother or
      sister; especially, the son or daughter of an uncle or
      aunt.
      1913 webster

   note: the children of brothers and sisters are usually
         denominated first cousins, or cousins-german. in
         the second generation, they are called second
         cousins. see cater-cousin, and quater-cousin.
         1913 webster

               thou art, great lord, my father's sister's son,
               a cousin-german to great priam's seed. --shak.
         1913 webster

   2. a title formerly given by a king to a nobleman,
      particularly to those of the council. in english writs,
      etc., issued by the crown, it signifies any earl.
      1913 webster

            my noble lords and cousins, all, good morrow.
                                                  --shak.
      1913 webster
see also:
sister cozen coz first cousins cousins-german second cousins 
cater-cousin quater-cousin