Breishit Rabbah 14:9 states, “She (the soul) has five names; Nephesh, Ruach, Neshama, Chaya, Yechidah. (The first is termed) Nephesh (which) is the blood, as is written “For the blood is the Nephesh” (Deut. 12:23). (The next is termed) Ruach for it rises and descends, as is written “Who knows the Ruach of men that rises on high” (Eccl. 3:21). (The third is termed) Neshama (which) is the disposition, for as people say, ‘His disposition is good’. (The fourth is termed) Chaya for all the limbs die and she lives on in the body. (And the fifth is termed)Yechidah for all the limbs have doubles while she is unique in the body.”
Also see Devarim Rabbah 2:37, Zohar 2:158b; Zohar Chadash 91a, and Sefer Bahir 53.