Waver

balancearse

(to sway back and forth, as if about to fall — see also reel, stagger, totter)

flaquear

(to begin to weaken or show signs of weakening in resolve — see also falter, flinch, give way)

fluctuar

(chiefly of a quality or thing: to change, to fluctuate, to vary — see also change, fluctuate, vary)

ondear

(to sway back and forth, as if about to fall — see also reel, stagger, totter)

oscilar

(chiefly of a quality or thing: to change, to fluctuate, to vary — see also change, fluctuate, vary)

vacilar

(to begin to weaken or show signs of weakening in resolve — see also falter, flinch, give way)

variar

(chiefly of a quality or thing: to change, to fluctuate, to vary — see also change, fluctuate, vary)