geriatrics, geriatric, geriatry 1. The branch of medicine that deals with the illnesses and medical care of senior citizens. 2. The branch of medicine concerned with the medical problems and care of the aged. Included are all aspects of aging, including physiological, pathological, psychological, economic, and sociological problems. The importance ... Found on http://www.wordinfo.info/words/index/info/view_unit/905/