adjective in·firm \in-ˈfərm\

: having a condition of weakness or illness that usually lasts for a long time and is caused especially by old age

Full Definition of INFIRM

:  of poor or deteriorated vitality; especially :  feeble from age
:  weak of mind, will, or character :  irresolute, vacillating
:  not solid or stable :  insecure
in·firm·ly adverb

Origin of INFIRM

Middle English, from Latin infirmus, from in- + firmus firm
First Known Use: 14th century

Synonym Discussion of INFIRM

weak, feeble, frail, fragile, infirm, decrepit mean not strong enough to endure strain, pressure, or strenuous effort. weak applies to deficiency or inferiority in strength or power of any sort <felt weak after the surgery>. feeble suggests extreme weakness inviting pity or contempt <a feeble attempt to walk>. frail implies delicacy and slightness of constitution or structure <a frail teenager unable to enjoy sports>. fragile suggests frailty and brittleness unable to resist rough usage <a reclusive poet too fragile for the rigors of this world>. infirm suggests instability, unsoundness, and insecurity due to old age or crippling illness <infirm residents requiring constant care>. decrepit implies being worn-out or broken-down from long use or old age <the dowager's decrepit retainers>.

Other Medicine Terms

analgesia, angina, diabetes, hepatitis, homeopathy, logorrhea, palliate, pandemic
INFIRM Defined for Kids


adjective in·firm \in-ˈfərm\

Definition of INFIRM for Kids

:  weak or frail in body
Medical Dictionary


adjective in·firm \in-ˈfərm\

Medical Definition of INFIRM

:  of poor or deteriorated vitality; especially :  feeble from age


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