ep·​si·​lon | \ˈep-sə-ˌlän, -lən\

Definition of epsilon 

1 : the 5th letter of the Greek alphabet — see Alphabet Table

2 : an arbitrarily small positive quantity in mathematical analysis

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Other Words from epsilon

epsilonic \ˌep-​sə-​ˈlä-​nik \ adjective

Examples of epsilon in a Sentence

Recent Examples on the Web

Based on the Greek letter epsilon, the euro symbol represents the coming together of nations. Patrick Di Justo, WIRED, "Europe on €10 a Day," 1 Jan. 2002

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'epsilon.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of epsilon

15th century, in the meaning defined at sense 1

History and Etymology for epsilon

Greek e psilon, literally, simple e

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Time Traveler for epsilon

The first known use of epsilon was in the 15th century

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More from Merriam-Webster on epsilon

Rhyming Dictionary: Words that rhyme with epsilon

Britannica.com: Encyclopedia article about epsilon

Comments on epsilon

What made you want to look up epsilon? Please tell us where you read or heard it (including the quote, if possible).


to move with a clumsy heavy tread

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