adjective
feeble
FEE-buhl/ˈfiːbl/
Weak in strength, force, or effectiveness.
The candle casts a feeble light that barely illuminates its surroundings.

Etymology
The pieces originally described something “to be wept over,” or lamentable. That sense developed into weakness, encompassing not only physical strength but also moral and intellectual vigor.
In context
he lit a lantern its feeble glow barely piercing the swirling Mist then as if summoned by the incantations he had learned
More examples
- His legs feel feeble after weeks in bed.
- She makes a feeble attempt to lift the suitcase.
- That is a feeble excuse for missing the deadline.
Forms
feeble · feebler · feeblest
feebly adverb — With little strength, force, or effectiveness.
feebleness noun — The condition of lacking strength or effectiveness.