I. ˈji-tər noun
Etymology: origin unknown
Date: 1929
1. plural : a sense of panic or extreme nervousness
had a bad case of the jitter s before his performance
2. : the state of mind or the movement of one that jitters
3. : irregular random movement (as of a pointer or an image on a television screen) ; also : vibratory motion
II. intransitive verb
Date: 1931
1. : to be nervous or act in a nervous way
2. : to make continuous fast repetitive movements