si

1 of 3

noun

Si

2 of 3

symbol

silicon

SI

3 of 3

abbreviation

International System of Units

Word History

Etymology

Noun

Italian

Abbreviation

French Système International d'Unités

First Known Use

Noun

1728, in the meaning defined above

Time Traveler
The first known use of si was in 1728

Dictionary Entries Near si

Cite this Entry

“Si.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/si. Accessed 22 Jul. 2024.

Kids Definition

si

noun
: the seventh note of a scale : ti

Medical Definition

Si

1 of 2 symbol
silicon

SI

2 of 2 abbreviation
International System of Units
Etymology

Abbreviation

French Système International d'Unités

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