The term Ra uses to refer to entities other than the self, i.e. I am your other-self, and you are my other-self. It is also a term that acknowledges the unity of all things, for each is a self, and each is an other-self to a self, and each is part of one self: the One Infinite Creator.
Reference
5.2, 12.13, 14.5, 15.4, 16.5, 17.2-3, 18.5-6, 18.12, 19.5, 20.26, 20.36, 25.1, 26.34, 26.38, 30.5, 30.10, 31.3, 32.1, 32.5-7, 32.9, 33.9, 33.11, 33.14-17, 34.5-6, 36.15, 38.5, 40.13, 41.4, 41.14, 42.10, 42.20, 42.3-4, 45.1, 46.9-10, 46.12, 47.13-14, 47.5, 48.6-7, 50.7, 52.9, 55.3, 56.3, 58.6, 60.8, 60.16, 61.6, 61.10, 64.5, 66.8-9, 67.7, 67.21, 68.18, 69.17, 71.5, 73.22, 74.9, 74.11, 76.3, 80.11, 82.17, 83.18, 83.27, 85.8, 86.20, 86.22, 87.21, 90.26, 99.8, 101.2, 101.8, 105.2