It's interesting to note that this original meaning has evolved over time to encompass the broader idea of "something that excites or incites to action".
So, "stimu" is a root that relates to excitation, arousal, or stimulation. This can be seen in words like:
* Stimulant: A substance that increases activity.
* Stimulate: To encourage or inspire activity.
* Stimulus: Something that causes a response or reaction.