lacking in volume, loudness, brightness, distinctness, etc.: a feeble voice; feeble light.
4.
lacking in force, strength, or effectiveness: feeble resistance; feeble arguments.
Origin: 1125–75; Middle English feble < Old French, variant of fleible (by dissimilation) < Latin flēbilis lamentable, equivalent to flē(re) to weep + -bilis-ble