Synonyms for Fastidious (same or very similar meaning)
WordNet sense 1 (having complicated nutritional requirements; especially growing only in special artificial cultures):
exacting
WordNet sense 2 (characterized by excessive precision and attention to trivial details):
persnickety, pernickety
WordNet sense 3 (marked by extreme care in treatment of details):
meticulous
WordNet sense 4 (exacting especially about details):
finicky, fussy, particular, picky, finical
WordNet sense 5 (excessively fastidious and easily disgusted):
dainty, nice, overnice, squeamish
From the ODE community, based on WordNet
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