The term "Semitic" refers to a language family that includes Hebrew, Arabic, and other related languages. It is separate from the lineage of Shem. Ashkenazi Jews are called "Semites" because they speak Yiddish, a language derived from Middle High German and influenced by Hebrew and other Semitic languages. This doesn't have any connection to Ashkenaz, mentioned in the Bible as a descendant of Japheth.