a) becomes aware that he or she is dreaming, and
b) achieves a degree of control over the content and direction of the dream.
Once an experienced lucid dreamer recognizes that she’s experiencing a dream, she is able to tailor the setting, the characters, and the action to suit her personal tastes.
2. A particularly vivid dream in which the dreamer himself appears. It is believed to be a form of astral projection, and if the dreamer can take conscious control of dream it then becomes a full out-of-body experience.