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Σ (シグマ) Japanese meaning | Kotomora

Σ

シ

グ

マ

Freq.FrequencyTop 10,000

Meanings

1

sigma

The 18th letter of the Greek alphabet; used in mathematics, science, and engineering.

数すう学がくでΣは総そう和わを表あらわす記き号ごうだ。
In mathematics, Σ is the symbol for summation.

Usage patterns

Σでしぐまで〈数すう〉の合計を表すのごうけいをあらわすto represent the sum of a set of numbers using sigma (Σ)
Σを使つかって1から10までの合ごう計けいを表あらわす。
We use sigma to represent the sum of the numbers from 1 to 10.

Don't confuse with

π
Π (パイ) denotes a product of a sequence in math notation, while Σ (シグマ) denotes a sum, so the two are easily confused as 'the other big Greek operator letter'.

Written forms

Σ
Uppercase sigma; standard mathematical and scientific notation.
σ
Lowercase sigma; used in statistics and physics.
ς
Final sigma; only used at the end of Greek words, rarely seen in Japanese contexts.

Etymology

From Greek σῖγμα (sigma), via English or other European languages.

この式しきのσは標ひょう準じゅん偏へん差さを意い味みしている。

The σ in this formula stands for standard deviation.