infirm

To be "infirm of purpose" is to be at the mercy of the artful or at the disposal of accident.

The contemplation of the infirm and lonely steed overcame him.

But the infirm are always cunning—he breathed not a suspicion.

Can they give beauty to the deformed, strength to the weak, or health to the infirm?

The Duke of Lerma, infirm and enfeebled by years, was unable to confront his foes.

Yet there are plenty of infirm people crawling about our streets.

Since she had been infirm, they had to attend to her like a child.

Alas for this infirm faith, this will not strenuous, this vast ebb of a vast flow!

There was, however, a tremble about the chin that told of infirm health.

Hugh Ritson faced about, leaning heavily on his infirm foot.