Amenorrhea meaning. Amenorrhea means the state of 'lacking menstrual periods'. If your periods were previously normal and now are gone, then you have 'secondary amenorrhea', meaning that you somehow lost ability to have normal periods. You need to see a doctor to determine the cause: ovarian dysfunction (pregnancy, menopause, pcos, etc) or pituitary problems (high prolactin, athletic amenorrhea, pituitary mass, etc).
Depends on cause. If the cause of the amenorrhea (loss of periods) is reversible, then your periods may come back.