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

Simple Definition of fastidious

  • : very careful about how you do something

  • : liking few things : hard to please

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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of fastidious

  1. 1 archaic :  scornful

  2. 2 a :  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> b :  showing or demanding excessive delicacy or care c :  reflecting a meticulous, sensitive, or demanding attitude <fastidious workmanship>

  3. 3 :  having complex nutritional requirements <fastidious microorganisms>

fastidiously adverb
fastidiousness noun

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. Judis, New Republic, 14 Oct. 1996

  2. “I'll stop off and get us a sandwich,” said Matthew. … Tony, a fastidious eater, sighed. —Penelope Lively, City of the Mind, 1991

  3. Though he prides himself on being hip, he is too fastidious to do anything dangerous or dirty. —Jay McInerney, Bright Lights, Big City, 1984

  4. He is fastidious about keeping the house clean.

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

Did You Know?

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 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

First Known Use: 15th century

Rhymes with fastidious

FASTIDIOUS Defined for Kids


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

Definition of fastidious for Students

  1. :  hard to please :  very particular <a fastidious dresser>

Medical Dictionary


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

Medical Definition of fastidious

  1. :  having complex nutritional requirements <fastidious microorganisms>—used of bacteria that grow only in specially fortified artificial culture media

Seen and Heard

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to expose to danger or risk

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