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sigma

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noun sig·ma \ˈsig-mə\

Simple Definition of sigma

  • : the 18th letter of the Greek alphabet

Source: Merriam-Webster's Learner's Dictionary

Full Definition of sigma

  1. 1 :  the 18th letter of the Greek alphabet — see alphabet table

  2. 2 :  standard deviation

Origin and Etymology of sigma

Greek


First Known Use: 1584


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