omega

noun

ome·​ga ō-ˈmā-gə  -ˈmē-  -ˈme- 

plural omegas

1

: the 24th and last letter of the Greek alphabet see Alphabet Table

2

: the extreme or final part : end compare alpha see also alpha and omega

3

: something or someone designated with the name omega or the Greek letter ω especially denoting the last in position, order, or class

"Omega-3" refers to the position of the final double bond in the chemical structure, which is three carbon atoms from the "omega," or tail end of the molecular chain.

—Ruairi Robertson

4

a

: a negatively charged elementary particle that has a mass 3270 times the mass of an electron

called also omega minus

b

: a very short-lived unstable meson with mass 1532 times the mass of an electron

called also omega meson

Word History

Etymology

Middle English, from Greek ō mega, literally, large o

First Known Use

15th century, in the meaning defined at sense 1

Phrases Containing omega

• alpha and omega
• the alpha and omega

Kids Definition

omega

noun

ome·​ga ō-ˈmeg-ə  -ˈmē-gə  -ˈmā-gə 

: the 24th and last letter of the Greek alphabet

—Ω or ω

Etymology

from Greek ō mega, literally, "big o"

Medical Definition

omega

adjective

ome·​ga

variants or ω-

ō-ˈmeg-ə, -ˈmā-gə, especially British ˈō-meg-ə

: of, relating to, or being a chemical group or position at the end of a molecular chain

omega oxidation of fatty acids