fas·tid·i·ous adjective \fa-ˈsti-dē-əs, fə-\: very careful about how you do something: liking few things : hard to please: wanting to always be clean, neat, etc.
c: reflecting a meticulous, sensitive, or demanding attitude <fastidious workmanship>. 3: having complex nutritional requirements <fastidious microorganisms>.
— fas·tid·i·ous·ly adverb
— fas·tid·i·ous·ness noun
Definition source: http://www.merriam-webster.com
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