Eta vs. Epsilon — What's the Difference?

Eta (uppercase Η, lowercase η; Ancient Greek: ἦτα ē̂ta [ɛ̂ːta] or Greek: ήτα ita [ˈita]) is the seventh letter of the Greek alphabet. Originally denoting the consonant /h/, its sound value in the classical Attic dialect of Ancient Greek was a long vowel [ɛː], raised to [i] in hellenistic Greek, a process known as iotacism.

Epsilon (UK: , US: ; uppercase Ε, lowercase ε or lunate ϵ; Greek: έψιλον) is the fifth letter of the Greek alphabet, corresponding phonetically to a mid front unrounded vowel /e/. In the system of Greek numerals it also has the value five.

The seventh letter of the Greek alphabet. See Table at alphabet.

The fifth letter of the Greek alphabet. See Table at alphabet.

The seventh letter of the Modern Greek alphabet, the eighth in Old Greek.

The name for the fifth letter of the Greek alphabet, ε or Ε, preceded by delta (Δ, δ) and followed by zeta (Ζ, ζ).

(particle) A kind of electrically neutral meson having zero spin and isospin.

(phonetics) In IPA, the phonetic symbol ɛ that represents the open-mid front unrounded vowel.

A social outcast in Japan who is subjected to menial work, making up a class or caste of such people.

(mathematics) An arbitrarily small quantity.

A terrorist organization organized in 1959 by student activists who were dissatisfied with the moderate nationalis of the traditional Basque party; want to create on independent homeland in Spain's western Pyrenees;

(colloquial) A small child.

The 7th letter of the Greek alphabet

Something negligible or insignificant.

(finance) The percentage change in an option value with respect to the underlying dividend yield.

The 5th letter of the Greek alphabet