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1

# infinitesimal

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noun in·fin·i·tes·i·mal \(ˌ)in-ˌfi-nə-ˈte-sə-məl, -zə-məl\

## Definition of infinitesimal

1. :  an infinitesimal quantity or variable

## Origin and Etymology of infinitesimal

New Latin infinitesimus infinite in rank, from Latin infinitus

First Known Use: 1706

2

## Simple Definition of infinitesimal

• : extremely small

Source: Merriam-Webster's Learner's Dictionary

## Full Definition of infinitesimal

1. 1 :  taking on values arbitrarily close to but greater than zero

2. 2 :  immeasurably or incalculably small <an infinitesimal difference>

## Examples of infinitesimal in a sentence

1. an infinitesimal moment in time

2. <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

1710

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## Definition of infinitesimal for Students

1. :  extremely small <The chance of winning is infinitesimal.>

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