Jitter is a modern word, first used in 1929.

The late Don Knotts was a superb actor. In his roles like the hapless Deputy Barney Fife, he epitomized jitter.

15 minutes ago, CarlHoliday said:

Luckily, my jitters, caused by a medical condition called essential tremor, are only a problem with use. You probably wouldn't notice it, unless you asked me to take a full cup of coffee across the room. In all likelihood, the cup would be less than half-full or empty at the end of the mission. It's mostly the fine movements that are affected the most. Like screwing a bottle cap back on or pausing in typing and hitting a key anyway. Getting the two parts of a zipper together is a challenge, as is grooming facial hair. And why essential? It's idiopathic. Now, there's a word for Word of the Day.

I have essential tremor also. It can be frustrating trying to accomplish simple tasks.