Definition of tremble :
1. An involuntary shaking or quivering.
2. To quaver or shake, as sound; to be tremulous; as the voice trembles.
3. To shake involuntarily, as with fear, cold, or weakness; to quake; to quiver; to shiver; to shudder; - said of a person or an animal.
4. To totter; to shake; - said of a thing.
milkshake, joggle, handshake, fidget, jar, shingle, frisson, reel, waggle, twitter, trill, heebie-jeebies, quake, shake, quaver, shudder, flap, chill, jolt, calm, fear, jounce, repetition, didder, swing, shiver, jim-jams, jitter, jump, handshaking, thrill, willies, all-overs, tingle, brandish, handclasp, milk shake, agitate
flicker (part of speech: verb)
oscillate (part of speech: verb)