fas·tid·i·ous (fā-stĭd'ē-əs, fə-) adj.
1. Possessing or displaying careful, meticulous attention to detail.
2. Difficult to please; exacting.
3. Excessively scrupulous or sensitive, especially in matters of taste or propriety.
4. Microbiology: having complicated nutritional requirements.
[Middle English, squeamish, particular, haughty, from Old French fastidieux, from Latin fastīdiōsus, from fastīdium, squeamishness, haughtiness, probably from fastus, disdain.]