si

¹ American  

[see] / si /

noun

Music.

1. the syllable used for the seventh tone of a scale and sometimes for the tone B.

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Si ² American  

Symbol, Chemistry.

1. silicon.

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SI ³ American  

abbreviation

1. International System of Units.

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S.I. ⁴ American  

abbreviation

1. Sandwich Islands.

2. Staten Island.

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SI ¹ British  

symbol

1. Système International (d'Unités) See SI unit

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abbreviation

1. South Island

Si ² British  

/ ʃiː /

noun

1. a variant transliteration of the Chinese name for the Xi

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Si ³ British  

symbol

1. silicon

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si ⁴ British  

/ siː /

noun

1. music a variant of te

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si ⁵ British  

abbreviation

1. Slovenia

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Etymology

Origin of si

First recorded in 1720–30; see origin at gamut

Example Sentences

Al alinearlo como titular, también se eliminan las complicaciones que supondría buscarle tiempo para calentar si su turno al bate llegara en la entrada anterior, algo que podría haberle dificultado cerrar el partido.

From Los Angeles Times • Nov. 1, 2025

She claims she even uses words and mannerisms such as "mamma mia", "bambino" and "si" in conversation without realising it.

From BBC • Dec. 22, 2024

Para muchos investigadores, la gran pregunta es si, de ser electa, Sheinbaum Pardo continuará, revisará, o incluso revertirá las impopulares políticas relacionadas con la ciencia de su mentor.

From Science Magazine • May 8, 2024

“Vacúnate como regalo de Año Nuevo si aún no lo has hecho”, dijo Schaffner.

From New York Times • Dec. 31, 2023

I tear a page out of my notebook and write: Ikik si naem.

From "Muffled" by Jennifer Gennari