Spindly vs Weakened - What's the difference?

As adjectives the difference between spindly and weakened

is that spindly is characteristic of a spindle; slender and of weak appearance while weakened is reduced, made less strong.

(weaken).

(er)

Characteristic of a spindle; slender and of weak appearance.

She has spindly legs.

(en adjective)

Reduced, made less strong.

His weakened immune system couldn't cope with the infection.

(head)

(weaken)