epsilon

[ ep-suh-lon, -luhn or, especially British, ep-sahy-luhn ]

/ ˈɛp səˌlɒn, -lən or, especially British, ɛpˈsaɪ lən /

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noun

the fifth letter of the Greek alphabet (E, ε).

the consonant sound represented by this letter.

Mathematics. an arbitrarily small quantity, used to indicate that a given quantity is small, or close to zero.

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Origin of epsilon

First recorded in 1400–50; from Greek e psīlón “bare, simple e” (as opposed to diphthongal spellings which in later Greek represented the same sound)

Words nearby epsilon

EPR, E-Prime, EPROM, eprosartan mesylate, EPS, epsilon, epsilon-delta, epsilon-neighborhood, Epsom, epsomite, Epsom salt

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use epsilon in a sentence

Lohse rushes Sigma Alpha Epsilon, gets a bid, endures pledge term, and then submits to the dehumanizing rigors of Hell Night.
An Ivy League Frat Boy’s Shallow Repentance|Stefan Beck|November 24, 2014|DAILY BEAST
Pledging, also known as initiation, will now be abolished by Sigma Alpha Epsilon nationally across its 240 chapters.
Deadly Frat Rituals Are Banned Thanks to Technology|Joe Concha|March 10, 2014|DAILY BEAST
The fraternities involved in the alleged drug sales were Alpha Epsilon Pi, Pi Kappa Alpha and Psi Upsilon.
Columbia University Drug Bust|Joshua Robinson, Lloyd Grove|December 8, 2010|DAILY BEAST
Gray broke the color barrier when he pledged Tau Epsilon Phi.
A Talk with D.C.'s New Mayor|Sandra McElwaine|November 2, 2010|DAILY BEAST

Kenny Luong died trying to start a Lambda Phi Epsilon chapter at California State Polytechnical University in Pomona, Calif.
The New Animal Houses|Dan Haley|March 22, 2009|DAILY BEAST
A few meager drops of rain, sibilantly soaking into the eager soil of Epsilon-Terra.
Attrition|Jim Wannamaker
Next look at Epsilon (ε), and you will find near it two seventh-magnitude companions, making a beautiful little triangle.
Astronomy with an Opera-glass|Garrett Putman Serviss
Now direct your glass to the northernmost of the two little stars near Vega, the one marked Epsilon (ε) in the map.
Astronomy with an Opera-glass|Garrett Putman Serviss
Turn your glass upon the star shown in the map just above Mu (μ) and Epsilon (ε).
Astronomy with an Opera-glass|Garrett Putman Serviss
The fact still remains that Epsilon had better be habitable or Pan-Asia will scream we're hogging it.
Competition|James Causey

British Dictionary definitions for epsilon (1 of 2)

epsilon

/ (ˈɛpsɪˌlɒn, ɛpˈsaɪlən) /

noun

the fifth letter of the Greek alphabet (Ε, ε), a short vowel, transliterated as e

Word Origin for epsilon

Greek e psilon, literally: simple e

British Dictionary definitions for epsilon (2 of 2)

Epsilon

/ (ˈɛpsɪˌlɒn, ɛpˈsaɪlən) /

noun

(foll by the genitive case of a specified constellation) the fifth brightest star in a constellationEpsilon Aurigae

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for epsilon (1 of 2)

The Greek letter epsilon. Entries beginning with this character are alphabetized under epsilon.

The symbol formolar absorption coefficient

Medical definitions for epsilon (2 of 2)

epsilon

[ ĕp′sə-lŏn′, -lən ]

The fifth letter of the Greek alphabet.

The fifth in a series.

adj.

Of or relating to the fifth member of a particular ordered set.

Relating to or characterizing a polypeptide chain that is one of five types of heavy chains present in immunoglobins.