german (adj.) Look up german at Dictionary.com
"of the same parents or grandparents," c.1300, from Old French germain "closely related" (12c.), from Latin germanus "full, own (of brothers and sisters); one's own brother; genuine, real," related to germen (genitive germinis) "sprout, bud," dissimilated from PIE *gen(e)-men-, from root *gene- "to give birth, beget" (see genus). Your cousin-german (also first cousin) is the son or daughter of an uncle or aunt; your children and your first cousin's are second cousins to one another; to you, your first cousin's children are first cousin once removed.
German (n.) Look up German at Dictionary.com
"Teuton, member of the Germanic tribes," 1520s (plural Germayns attested from late 14c.), from Latin Germanus, first attested in writings of Julius Caesar, who used Germani to designate a group of tribes in northeastern Gaul, origin unknown, probably the name of an individual tribe. It is perhaps of Gaulish (Celtic) origin, perhaps originally meaning "noisy" (compare Old Irish garim "to shout") or "neighbor" (compare Old Irish gair "neighbor"). The earlier English word was Almain (early 14c.) or Dutch. In Finnish, Germany is Saksa "Land of the Saxons."
Þe empere passede from þe Grees to þe Frenschemen and to þe Germans, þat beeþ Almayns. [John of Trevisa, translation of Higdon's Polychronicon, 1387]
Their name for themselves was the root word of modern German Deutsch (see Dutch). Roman writers also used Teutoni as a German tribal name, and Latin writers after about 875 commonly refer to the German language as teutonicus. See also Alemanni and Teutonic. As an adjective, from 1550s. The German shepherd (dog) (1922) translates German deutscher Schäferhund. German Ocean as an old name for the North Sea translates Ptolemy. German measles attested by 1856.