Emily Dickinson Lexicon

FAS-TID'I-OUS, a. [L. fastidiosus, from fastidio, to disdain, from fastus, haughtiness. See Heb. בוז. Class Bz, No. 2, 3, 10, 30.]

1. Disdainful; squeamish; delicate to a fault; over nice; difficult to please; as, a fastidious mind or taste.
2. Squeamish; rejecting what is common or not very nice; suited with difficulty; as, a fastidious appetite.