infirm

Weak in body or mind, especially from old age or disease. synonym: weak.

Not strong or stable; shaky.

Lacking firmness of will, character, or purpose; irresolute.

To weaken; enfeeble.

To make less firm or certain; render doubtful, questionable, or dubious.

Not firm, stable, or strong; lacking stability or solidity; faltering; feeble: as, an infirm support; an infirm judgment.

Specifically Not sound in health; impaired in health or vitality; enfeebled; weak: as, infirm in body or constitution.

Voidable; obnoxious to legal objection that may destroy apparent efficacy.

Not firm or sound; weak; feeble

Weak of mind or will; irresolute; vacillating.