The definition of fastidious is a very careful attention to detail, or an uptight or hyper-critical person.(adjective)
An example of fastidious is a guest looking for dust on surfaces in another's home.
See fastidious in Webster's New World College Dictionary
Origin: ME < L fastidiosus < fastidium, a loathing, disgust < fastus, disdain, contempt, pride (< ? IE base *bhars-, projection, point, bristle) + taedium: see tedium
See fastidious in American Heritage Dictionary 4
Origin: Middle English, squeamish, particular, haughty
Origin: , from Old French fastidieux
Origin: , from Latin fastīdiōsus
Origin: , from fastīdium, squeamishness, haughtiness
Origin: , probably from fastus, disdain.
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