Susa: the ancient royal city in what is now southwestern Iran, a residence of the Persian kings and the setting of the book of Esther.
Susa (older English versions call it Shushan) was one of the oldest cities of the ancient Near East. It began as the capital of Elam and later became one of the chief royal residences of the Persian Empire, so that its fortified upper city, the citadel, is where a Persian king holds court in the Bible.
Every time the word appears it names this one place. It is the stage on which the whole story of Esther unfolds, from the king's banquet to the rescue of the Jews and the first keeping of Purim. Daniel is carried there in a vision and sees himself beside the Ulai canal, and Nehemiah is living in Susa when he first hears that Jerusalem lies in ruins.
The name comes from the city's own ancient language, and it is far older than Israel. By an accident of spelling, in Hebrew the city's name looks exactly like the ordinary word for a lily (shoshan). The two are not actually related: the resemblance is a coincidence of sound, not a shared origin. Later Jewish tradition enjoyed playing on the likeness, but the play is a pun, not a real family tie.