Webster’s Revised Unabridged Dictionary · 1913
Infirm
In·firm′ (ĭn·fẽrm′), a. [L. infirmus: cf. F. infirme. See In- not, and Firm, a.] 1. Not firm or sound; weak; feeble; as, an infirm body; an infirm constitution.
A poor, infirm, weak, and despised old man. Shak.
2. Weak of mind or will; irresolute; vacillating. "An infirm judgment." Burke.
Infirm of purpose! Shak.
3. Not solid or stable; insecure; precarious.
He who fixes on false principles treads or infirm ground. South.
Syn. — Debilitated; sickly; feeble; decrepit; weak; enfeebled; irresolute; vacillating; imbecile.
In·firm′, v. t. [L. infirmare : cf. F. infirmer.] To weaken; to enfeeble. [Obs.] Sir W. Raleigh.