noun Uncommon

sigma

SIHG-muh

Sigma (noun) means the eighteenth letter of the Greek alphabet (Σ, σ). Example: “Sigma appears in the equation as the summation symbol.”

noun

The eighteenth letter of the Greek alphabet (Σ, σ).

"Sigma appears in the equation as the summation symbol."

In statistics, the symbol used to represent standard deviation from a mean.

"The result fell within two sigma of the expected value."

Slang for a self-reliant, emotionally detached man who operates outside conventional social hierarchies (a "sigma male").

"The video jokingly called the lone wolf character a total sigma."

How to use sigma

Learner’s notes

In plain EnglishA Greek letter used heavily in maths and science for summation and standard deviation, and, in recent internet slang, a personality-type label.

When to use it

The "sigma male" sense is internet slang and best kept to casual or ironic contexts.

Word forms

more sigma comparative, sigmas plural, sigmata plural, most sigma superlative

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_____ appears in the equation as the summation symbol.

Etymology

From Ancient Greek sigma, likely from a root associated with hissing sounds, referencing the letter's "s" sound.

Origin: Ancient Greek

Rhymes for sigma

stigma Enigma

See all rhymes for sigma →

Frequently asked questions

What does “sigma” mean?

The word “sigma” means the eighteenth letter of the Greek alphabet (Σ, σ). In plain terms, a Greek letter used heavily in maths and science for summation and standard deviation, and, in recent internet slang, a personality-type label.

How do you pronounce “sigma”?

“Sigma” is pronounced SIHG-muh (/ˈsɪɡmə/ in IPA).

How do you use “sigma” in a sentence?

Here is “sigma” used in a sentence: “Sigma appears in the equation as the summation symbol.”

What part of speech is “sigma”?

“Sigma” is a noun.

Where does the word “sigma” come from?

The word “sigma” comes from Ancient Greek. From Ancient Greek sigma, likely from a root associated with hissing sounds, referencing the letter's "s" sound.

Is “sigma” a common word?

“Sigma” is an uncommon word in modern English.

How many meanings does “sigma” have?

“Sigma” has 3 distinct senses listed in this dictionary. The most common is: the eighteenth letter of the Greek alphabet (Σ, σ).