Wu is a Chinese term translating to "shaman" or "sorcerer", originally the practitioners of Chinese shamanism or "Wuism".
Han dynasty tomb-tile showing "long-sleeved dancers" and attendants.
A xian is any manner of immortal, mythical being within the Taoist pantheon or Chinese folklore. Xian has often been translated into English as "immortal".
"The Eight Immortals Crossing the Sea"
Immortal riding a Dragon, by Ma Yuan.
Xian as depicted on Eighty-seven Immortals (八十七神仙), popularly attributed to Tang dynasty painter Wu Daozi, currently housed in Xu Beihong Memorial Hall in Beijing.
Xiwangmu descends from heavens with a Peach of Immortality (Jade Pond Birthday greeting, by Jin Tingbiao, Qing dynasty