sigma

σ

, Σ

1. The 18th letter of the Greek alphabet, sigma.

2. (σ) Symbol for reflection coefficient; standard deviation; a factor in prokaryotic RNA initiation; wavenumber; surface tension.

3. (Σ) Summation of a series.

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sig·ma

(sig'mă),

The 18th letter of the Greek alphabet, σ.

sigma

(sĭg′mə)

n.

A sigma factor.

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sig′mate′ (-māt′) adj.

sigma

[sig′mə]

Σ, σ, and s, the eighteenth letter of the Greek alphabet.

σ

Abbreviation for standard deviation; reflection coefficient.

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sig·ma

(σ,Σ) (sig'mă)

1. The 18th letter of the Greek alphabet.

2. (σ) reflection coefficient;standard deviation; a factor in prokaryotic RNA initiation; surface tension

3. (Σ) Summation of a series.

sig·ma

(sig'mă)

1. The 18th letter of the Greek alphabet (σ, Σ).

2. (σ) reflection coefficient; standard deviation; a factor in prokaryotic RNA initiation; surface tension

3. (Σ) Summation of a series.

sigma

the Greek letter σ or σ; the former frequently denotes a standard deviation, the latter is used in mathematics for the sum of the values of the term nominated.