infirm
adjective formal uk/ɪnˈfɜːm/ us/ɪnˈfɝːm/
（尤指因年迈而长期）病弱的，需要照顾的
ill or needing care, especially for long periods and often because of old age
She was too elderly and infirm to remain at home. 她过于年老体弱而无法继续住在家里。
infirm
noun [ plural ] formal uk/ɪnˈfɜːm/ us/ɪnˈfɝːm/
the infirm 体弱的人
people who are ill for long periods
The old and the infirm are the most susceptible to this disease. 年老体弱者最容易得这种病。