Definition of infinitesimal
: an infinitesimal quantity or variable
Origin and Etymology of infinitesimal
New Latin infinitesimus infinite in rank, from Latin infinitus
First Known Use: 1706
Other Mathematics and Statistics Terms
infinitesimal
Definition of infinitesimal
1 : taking on values arbitrarily close to but greater than zero
2 : immeasurably or incalculably small <an infinitesimal difference>
Examples of infinitesimal in a sentence
an infinitesimal moment in time
<a soft drink with only an infinitesimal amount of caffeine>
Did You Know?
Infinite, as you probably know, means "endless" or "extending indefinitely." It is ultimately from Latin infinitus, the opposite of finitus, meaning "finite." The notion of smallness in infinitesimal derives from the mathematical concept that a quantity can be divided endlessly; no matter how small, it can be subdivided into yet smaller fractions, or "infinitesimals." The concept was still in its infancy in 1710 when Irish philosopher George Berkeley observed that some people "assert there are infinitesimals of infinitesimals of infinitesimals, etc., without ever coming to an end." He used the adjective in a mathematical sense, too, referring to "infinitesimal parts of finite lines." Less than a quarter century later, the adjective had acquired a general sense applicable to anything too small to be measured.
1710
First Known Use of infinitesimal
1710
Other Mathematics and Statistics Terms
INFINITESIMAL Defined for English Language Learners
infinitesimal
Definition of infinitesimal for English Language Learners

: extremely small
INFINITESIMAL Defined for Kids
infinitesimal
playDefinition of infinitesimal for Students
: extremely small <The chance of winning is infinitesimal.>
Learn More about infinitesimal

Thesaurus: All synonyms and antonyms for infinitesimal Spanish Central: Translation of infinitesimal Nglish: Translation of infinitesimal for Spanish speakers Britannica.com: Encyclopedia article about infinitesimal
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