To shake involuntarily, typically as a result of anxiety, excitement, or frailty. She began to tremble with fear as she heard the thunder.
To be affected with great fear or apprehension. He trembled at the thought of speaking in front of the large audience.
To shake or quiver slightly, especially of an inanimate object, surface, or voice, as if vibrated by an external force. The leaves trembled in the autumn breeze.