Collins Russian Dictionary 2nd Edition © HarperCollins Publishers 2000, 1997:
Greek [griːk] adj гре́ческий
n (person) грек/греча́нка* (LING) гре́ческий*язы́к#
ancient/modern Greek древнегре́ческий*совреме́нный гре́ческий*язы́к#
* is used to mark translations which have irregular inflections. The Russian-English side of the dictionary gives inflectional information.