tremble precariously (verb) teeter: wobble back and forth
Sinonime: balance, dangle,
falter,
flutter, lurch,
pivot,
quiver, reel,
rock, seesaw,
stagger, stammer,
stumble,
sway, teeter-totter, topple, totter,
tremble, tremble precariously,
waver,
weave, wiggle
Antonime: stabilize,
steady