Self
Part of speech: noun
Definition: An individual person as the object of his own reflective consciousness.
Part of speech: adjective
Definition: same
Example sentence: Above all the grace and the gifts that Christ gives to his beloved is that of overcoming self.
Ego
Part of speech: noun
Definition: The self, especially with overtones of self-importance.The most conscious part of the mind, which mediates with one's surroundings.
Example sentence: Fear seems to have many causes. Fear of loss, fear of failure, fear of being hurt, and so on, but ultimately all fear is the ego's fear of death, of annihilation. To the ego, death is always just around the corner. In this mind-identified state, fear of death affects every aspect of your life.