adjective fas·tid·i·ous \ fa-ˈsti-dē-əs , fə- \
|Updated on: 19 Jul 2018

Definition of fastidious

1 a : showing or demanding excessive delicacy or care
  • fastidious attention to detail
  • —Robert Evett
b : reflecting a meticulous, sensitive, or demanding attitude
  • fastidious workmanship
c : having high and often capricious standards : difficult to please
  • critics … so fastidious that they can talk only to a small circle of initiates
  • —Granville Hicks
2 : having complex nutritional requirements
  • fastidious microorganisms
3 archaic : scornful





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Examples of fastidious in a Sentence

  1. My mother had always been the most fastidious and organized of people—a wet ring left on her coffee table by a glass could drive her to distraction. —John B. JudisNew Republic14 Oct. 1996
  2. "I'll stop off and get us a sandwich," said Matthew.  … Tony, a fastidious eater, sighed. —Penelope LivelyCity of the Mind1991
  3. Though he prides himself on being hip, he is too fastidious to do anything dangerous or dirty. —Jay McInerneyBright Lights, Big City1984
  4. He is fastidious about keeping the house clean.

  5. She was too fastidious to do anything that might get her dirty.

Recent Examples of fastidious from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fastidious.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

fastidious Has a Disgusting Past

There's nothing offensive about fastidious workmanship, and yet the word fastidious traces to the Latin noun fastidium, meaning "aversion" or "disgust." "Fastidium" itself is probably a combination of the Latin words fastus, meaning "arrogance," and taedium, meaning "irksomeness" or "disgust."("Taedium" also gave us our "tedium.") In keeping with its Latin roots, fastidious once meant "haughty," "disgusting," and "disgusted," although those uses are now archaic or obsolete. The word came to be applied to someone who is squeamish or overly difficult to please, and later, to work which reflects a demanding or precise attitude.

Origin and Etymology of fastidious

Middle English, from Latin fastidiosus, from fastidium disgust, probably from fastus arrogance (probably akin to Latin fastigium top) + taedium irksomeness — more at tedium

FASTIDIOUS Defined for English Language Learners


Definition of fastidious for English Language Learners

  • : very careful about how you do something

  • : liking few things : hard to please

  • : wanting to always be clean, neat, etc.

FASTIDIOUS Defined for Kids


adjective fas·tid·i·ous \ fa-ˈsti-dē-əs \

Definition of fastidious for Students

: hard to please : very particular
  • a fastidious dresser

Medical Dictionary


adjective fas·tid·i·ous \ fa-ˈstid-ē-əs, fə- \

medical Definition of fastidious

: having complex nutritional requirements
  • fastidious microorganisms
used of bacteria that grow only in specially fortified artificial culture media

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