infirm
adjective
[ ɪnˈfəːm ]
• not physically or mentally strong, especially through age or illness.
• "those who were old or infirm"
Similar:
frail,
weak,
feeble,
enfeebled,
weakly,
debilitated,
decrepit,
bedridden,
ill,
unwell,
sick,
sickly,
poorly,
indisposed,
in poor/declining health,
failing,
ailing,
doddering,
doddery,
tottering,
wobbly,
unsteady,
unstable,
Origin:
late Middle English (in the general sense ‘weak, frail’): from Latin infirmus, from in- ‘not’ + firmus ‘firm’.