jitters (n.)youdaoicibaDictYouDict[jitters 词源字典]
"extreme nervousness," 1925, American English, perhaps an alteration of dialectal chitter "tremble, shiver," from Middle English chittern "to twitter, chatter."[jitters etymology, jitters origin, 英语词源]
nerve (n.)youdaoicibaDictYouDict
late 14c., nerf "sinew, tendon," from Old French nerf and directly from Medieval Latin nervus "nerve," from Latin nervus "sinew, tendon; cord, bowstring," metathesis of pre-Latin *neuros, from PIE *(s)neu- "tendon, sinew" (cognates: Sanskrit snavan- "band, sinew," Armenian neard "sinew," Greek neuron "sinew, tendon," in Galen "nerve"). Sense of "fibers that convey impulses between the brain and the body" is from c. 1600.

Secondary senses developed from meaning "strength, vigor, energy" (c. 1600), from the "sinew" sense. Hence figurative sense of "feeling, courage," first attested c. 1600; that of "courage, boldness" is from 1809; bad sense "impudence, cheek" is from 1887. Latin nervus also had a figurative sense of "vigor, force, power, strength," as did Greek neuron. From the neurological sense come Nerves "condition of nervousness," attested from 1792; to get on someone's nerves, from 1895. War of nerves "psychological warfare" is from 1915.
nervous (adj.)youdaoicibaDictYouDict
c. 1400, "affecting the sinews," from Latin nervosus "sinewy, vigorous," from nervus "sinew, nerve" (see nerve). Meaning "of or belonging to the nerves" in the modern sense is from 1660s. Meaning "suffering disorder of the nervous system" is from 1734; illogical sense "restless, agitated, lacking nerve" is 1740. Widespread popular use as a euphemism for mental forced the medical community to coin neurological to replace it in the older sense. Nervous wreck first attested 1862. Related: Nervously; nervousness.
willies (n.)youdaoicibaDictYouDict
"spell of nervousness," 1896, perhaps from the woollies, a dialectal term for "nervous uneasiness," probably in reference to the itchiness of wool garments.
jim-jams (1)youdaoicibaDictYouDict
"A fit of depression or nervousness", Mid 16th century (originally denoting a small article or knick-knack): fanciful reduplication. The current sense dates from the late 19th century.