### Definition of Infinitesimal

1. Noun. (mathematics) a variable that has zero as its limit.

Generic synonyms: Variable, Variable Quantity
Category relationships: Math, Mathematics, Maths

2. Adjective. Infinitely or immeasurably small. "Reduced to a microscopic scale"
Exact synonyms: Minute
Similar to: Little, Small
Derivative terms: Minuteness

### Definition of Infinitesimal

1. a. Infinitely or indefinitely small; less than any assignable quantity or value; very small.

2. n. An infinitely small quantity; that which is less than any assignable quantity.

### Definition of Infinitesimal

1. Adjective. Incalculably, exceedingly, or immeasurably minute; vanishingly small. ¹

2. Adjective. (mathematics) Of or pertaining to values that approach zero as a limit. ¹

3. Adjective. (informal) Very small. ¹

4. Noun. (mathematics) A non-zero quantity whose magnitude is smaller than any positive number (by definition it is not a real number). ¹

¹ Source: wiktionary.com

1. [n -S]

### Medical Definition of Infinitesimal

1. An infinitely small quantity; that which is less than any assignable quantity. Source: Websters Dictionary (01 Mar 1998)

### Lexicographical Neighbors of Infinitesimal

 infinite distanceinfinite loopinfinite loopsinfinite monkey theoreminfinite recursioninfinite recursionsinfinite regressinfinite scrollinfinite seriesinfinite suicide infinite suicidesinfinitelyinfinitenessinfinitenessesinfinitesinfinitesimal (current term)infinitesimal analysisinfinitesimal calculusinfinitesimallyinfinitesimals infinitiesinfinitisminfinitivalinfinitivallyinfinitiveinfinitive of purposeinfinitivelyinfinitivesinfinitives of purposeinfinito

### Literary usage of Infinitesimal

Below you will find example usage of this term as found in modern and/or classical literature:

1. Dictionary of Philosophy and Psychology: Including Many of the Principal by James Mark Baldwin (1901)
"Quantities are not conceived in mathematics as having absolutely infinite or infinitesimal values. Quantities are compared by comparing their boundaries, ..."

2. Advanced Calculus: A Text Upon Select Parts of Differential Calculus by Edwin Bidwell Wilson (1912)
"infinitesimal analysis. To work rapidly in the applications of calculus to problems in geometry and physics and to follow readily the books -written on ..."

3. Encyclopaedia Britannica, a Dictionary of Arts, Sciences, Literature and edited by Hugh Chisholm (1910)
"-f^X, may then be regarded as denning the moat general infinitesimal operation of the group. In fact, if it be for a moment represented by X, ..."

4. Elements of the Differential Calculus: With Examples and Applications : a by William Elwood Byerly (1901)
"An infinitesimal or infinitely small quantity is a variable which is supposed to decrease indefinitely; in other words, it is a variable which approaches ..."

5. Elements of the Integral Calculus: With a Key to the Solution of by William Elwood Byerly (1892)
"The line integral of a function along a given line is absolutely independent of the manner in which the line is broken up into infinitesimal elements, ..."

6. Sophus Lie's 1880 transformation group paper by Sophus Lie, Robert Hermann (1975)
"Chapter 7 THE infinitesimal TRANSFORMATIONS OF A GROUP In the following we shall show that every r-term group in which every transformation has an inverse ..."

7. Introductory Treatise on Lie's Theory of Finite Continuous Transformation Groups by John Edward Campbell (1903)
"A transformation whose effect differs infinitesimally from the identical transformation is said to be an infinitesimal transformation. ..."