Origin: Its first usage dates back to 1611 and has originated from a Latin word Tremulus.
1) Characterized by tremors/trembling that is invoked by nervousness or fear
2) Trembling, shaking
3) Timid/shy or fearful
Tremulous can be learnt easily by associating it with an earthquake or the dizzy feeling that come in the event of an earthquake. The feeling of dizziness may also come for some in the event of fear or nervousness.