The Greek Elissaios is the transliteration of Hebrew Elisha — "God is salvation." Elisha was the successor of Elijah, the great miracle-working prophet of the Northern Kingdom (9th century BC). He appears once in the NT: Luke 4:27, where Jesus appeals to Elisha's healing of Naaman the Syrian leper to illustrate God's grace extending beyond ethnic Israel.
Jesus' mention of Elissaios (Elisha) in Luke 4:27 was deliberately provocative — and the synagogue responded with murderous rage (Luke 4:28–29). Why? Because Jesus used Elisha's healing of Naaman — a Gentile military commander — to argue that God's mercy is not confined to Israel. Elisha's ministry was marked by extraordinary miracles (double the "portion of the spirit" he requested of Elijah: 2 Kings 2:9), pointing forward to Jesus who performs these same works and more. His name (God is salvation) is his ministry in miniature.