n.the study of methods of improving human well-being and efficient functioning by improving environmental conditions
英汉双解大词典
euthenics/juːˈθɛnɪks/
1.
N（名词）
the study of the control of the environment, esp with a view to improving the health and living standards of the human race 优境学; 尤指为了改善人类健康和提高人类生活水准的环境控制学