Weak as a kitten

Origin

The enduring image of a newborn kitten—tiny, wobbly, and utterly dependent—provides the vivid foundation for this common English phrase. Kittens, fresh into the world, are all softness and uncoordinated movements, incapable of significant effort or resistance. This universal observation of their initial feebleness became a natural, widely understood benchmark for extreme lack of strength in humans or objects. The phrase, likely gaining widespread traction by the 19th century, concisely captures that profound sense of vulnerability and fragility, making it a powerful, relatable shorthand for someone who is completely exhausted or unwell.