Hellenists, Greek-Jews; Jews born in a foreign country, and thus did not speak Hebrew (Acts 6:1; 9:29), nor join in the Hebrew services of the Jews in Palestine, but had synagogues of their own in Jerusalem. Joel 3:6 =Greeks.
Easton’s Bible Dictionary
Grecians
Easton’s Bible Dictionary (1897), public domain. Text via Theographic Bible Metadata, CC BY-SA 4.0.