sigma

Ρρ$\longleftarrow$ 18 $\longrightarrow$Ττ

Pronunciation

• IPA ^(key): /ˈsɪɡmə/

• Audio (US)

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Noun

Singular sigma

Plural sigmas

sigma

1. Eighteen letter of Greek.
2. Σσ, and in the word last position, writes as ς.
3. Standard deviation,has formula $:={\displaystyle \sigma ={\sqrt {{\frac {1}{n}}\sum _{\iota =1}^{n}(a_{\iota }-{\bar {x}})^{2}}}}$ the average symbol ${\bar {x}}$ often writes as μ