infirm /ɪnˈfɚm/ adjective Learner's definition of INFIRM
[more infirm; most infirm]
: having a condition of weakness or illness that usually lasts for a long time and is caused especially by old age(长期)病弱的;(尤指因年老)体弱的
the infirm
: people who are weak, ill, etc. : infirm people病弱者;体弱者