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.

FEEBLE definition: physically weak, as from age or sickness; frail. See examples of feeble used in a sentence.

Feeble-minded children are defined as those who appear to be 'permanently incapable' of receiving proper benefit from teaching in ordinary schools.

Definition of feeble adjective in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.

1. physically weak, as from age or sickness; frail. 2. weak intellectually or morally: a feeble mind. 3. lacking in volume, brightness, distinctness, etc.: feeble light. 4. lacking in substance or effectiveness: …

There are 18 meanings listed in OED's entry for the word feeble, eight of which are labelled obsolete. See ‘Meaning & use’ for definitions, usage, and quotation evidence.

lacking in volume, loudness, brightness, distinctness, etc.: a feeble voice; feeble light. lacking in force, strength, or effectiveness: feeble resistance; feeble arguments.

Business is suffering because of the feeble economy. He made a feeble attempt/effort to explain his behavior. He offered a feeble excuse for his behavior. “Dislike” is too feeble a word for how she feels …

Wanting in force exerted, whether of action or resistance; lacking in intensity, vividness, energy, or efficiency; faint: as, a feeble voice; a feeble light; feeble thinking; a feeble argument or poem.

If you describe something that someone says as feeble, you mean that it is not very good or convincing. This is a particularly feeble argument.