epsilon

noun

ep·​si·​lon ˈep-sə-ˌlän 

-lən

plural epsilons

1

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

2

: something or someone designated with the name epsilon or the Greek letter ε especially denoting the fifth in position, order, or class

3

: an arbitrarily small positive quantity in mathematical analysis

epsilonic

ˌep-sə-ˈlä-nik 

adjective

Word History

Etymology

Greek e psilon, literally, simple e

First Known Use

15th century, in the meaning defined at sense 1

Kids Definition

epsilon

noun

ep·​si·​lon ˈep-sə-ˌlän 

-lən

: the 5th letter of the Greek alphabet

—Ε or ε