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infinitesimal Line breaks: in|fini|tesi¦mal
Pronunciation: /ˌɪnfɪnɪˈtɛsɪm(ə)l/

Definition of infinitesimal in English:


Extremely small: an infinitesimal pause
More example sentences
  • I seek leave to table from the New England Journal of Medicine a recent definitive study showing that intellectual impairment of children can occur even with extremely infinitesimal amounts of lead.
  • It was a pause so infinitesimal that I almost didn't catch it, but I knew what I glimpsed.
  • Minute, infinitesimal amounts of chemical contaminants crossing the placenta can cause cancer in young adults decades later.
minute, tiny, minuscule, extremely small, very small;
microscopic, nanoscopic, barely perceptible, imperceptible, inappreciable, indiscernible, invisible to the naked eye;
Scottish wee
British informal titchy
North American informal little-bitty


Mathematics Back to top  
An indefinitely small quantity; a value approaching zero.
Example sentences
  • These two concepts, infinitesimals and infinite quantities, however, were stirring great philosophical dilemmas.
  • The book shows how this notion can be used to form various kinds of infinities such as the projective plane, transfinite numbers, and infinitesimals.
  • Also in 1786 he again worked on his ideas for the differential and integral calculus, giving a new treatment of infinitesimals.


Mid 17th century: from modern Latin infinitesimus, from Latin infinitus (see infinite), on the pattern of centesimal.



Pronunciation: /ˌɪnfɪnɪˈtɛsɪm(ə)li/
Example sentences
  • The design of the pipeline means that the risk of such an event or any other type of gas escape is infinitesimally small.
  • In fact, leaving aside the infinitesimally small world of math geniuses, there isn't any evidence that men are more intelligent than women, and no one seriously says so.
  • At their best they became monolithic tomes - bunkers for content, guides updated haphazardly that infinitesimally accrete ‘content’.

Words that rhyme with infinitesimal


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Pronunciation: fôrˈtisəˌmō
(especially as a direction) very loud or loudly