The Romanian language has always been in a dynamic process of linguistic interference, favored by the geographical, political, economic, cultural context. Besides words, the Romanian language borrowed suffixes. One of them is the suffix -ache (-achi), which is of Greek origin. In the original language it formed only diminutives, especially from first names. Due to imposed strategies and family traditions, this suffix has experienced a period of prosperity throughout the Greek rule. During the evolution of our literary language it marked a separate period of Greek influence. Today the suffix -ache (-achi) doesn’t form new derivatives, but it is found in ready formations, namely in last names.