Definition of infinitesimal
: an infinitesimal quantity or variable
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Origin and Etymology of infinitesimal
New Latin infinitesimus infinite in rank, from Latin infinitus
First Known Use: 1706See Words from the same year
Definition of infinitesimal
1 : taking on values arbitrarily close to but greater than zero
2 : immeasurably or incalculably small an infinitesimal difference
infinitesimallyplay \(ˌ)in-ˌfi-nə-ˈte-sə-mə-lē, -zə-mə-\ adverb
Examples of infinitesimal in a Sentence
an infinitesimal moment in time
a soft drink with only an infinitesimal amount of caffeine
Recent Examples of infinitesimal from the Web
Note that around 17.5 million light-duty vehicles were sold last year, swelling the national fleet to more than 240 million vehicles, and only the most infinitesimal percentage of them has any autonomous ability whatsoever.
At the bottom of the pools are thousands of pebbles sparkling with velvety druzy — infinitesimal crystals that resemble pollen, or butterfly feathers, or book gilt.
But both sides of the debate agree the odds of this happening are infinitesimal.
In the grand scheme of Amazon’s business, analysts consider the retail stores to be an infinitesimal portion of the more than $135 billion in sales expected from the company this year.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'infinitesimal'. Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
What is the origin of infinitesimal?
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.
First Known Use of infinitesimal
INFINITESIMAL Defined for English Language Learners
Definition of infinitesimal for English Language Learners
: extremely small
INFINITESIMAL Defined for Kids
Definition of infinitesimal for Students
: extremely small The chance of winning is infinitesimal.
Seen and Heard
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