major adj.较多的；主要的；严重的；(音乐)大调的n.成年人；主修（科目）；陆军少校；举足轻重者v.主修
详细释义
Noun:
(psychiatry) a state of depression with all the classic symptoms (anhedonia and lethargy and sleep disturbance and despondency and morbid thoughts and feelings of worthlessness and sometimes attempted suicide) but with no known organic dysfunction
