adj
fastidious
fas-TIH-dee-uhs
adj
1
Extremely careful about small details, especially cleanliness and order; hard to please.
"She was fastidious about keeping her desk perfectly organised."
"He's so fastidious that he re-irons shirts that already look fine."
2
(biology) Needing very specific conditions or nutrients to grow, and therefore difficult to culture.
"The bacteria proved fastidious, requiring a special enriched growth medium in the lab."
How to Use Fastidious
Learner’s notesIn plain EnglishExtremely fussy and precise about details, order, or cleanliness.
Common mistake
Not the same as "fast" — the words share no real connection despite looking similar.
Common pairings
fastidious about detail
fastidiously clean
fastidious eater
Word Forms
more fastidious comparative, most fastidious superlative
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Etymology
From Latin fastidiosus ("disdainful, squeamish"), from fastidium ("disgust, distaste").