totter or waver

to totter or waver (through weakness of the legs, especially the ankle); by implication, to falter, stumble, faint or fall

bereave (from the margin), cast down, be decayed, (cause to) fail, (cause, make to) fall (down, -ing), feeble, be (the) ruin(-ed, of), (be) overthrown, (cause to) stumble, [idiom] utterly, be weak.