si

[ see ]

/ si /

noun Music.

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

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Origin of si

First recorded in 1720–30; see origin at gamut

Words nearby si

shylock, shymkent, shypoo, shyster, shīn, si, si derived unit, si quaeris peninsulam amoenam, circumspice, si unit, si-ma qian, siabon

Definition for si (2 of 4)

Symbol, Chemistry.

silicon.

Definition for si (3 of 4)

International System of Units.

Definition for si (4 of 4)

S.I.

Sandwich Islands.

Staten Island.

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Example sentences from the Web for si

Except for nine of them are musical words: do, re, mi, fa, so, la, ti—and si—are musical.
Well, La Ti Da: Stephin Merritt’s Winning Little Words of Scrabble|David Bukszpan|October 11, 2014|DAILY BEAST
Michael Sam has one big advantage over the aging NFL execs who whined to SI.
Michael Sam Is Not a ‘Distraction’|Dave Cullen|February 12, 2014|DAILY BEAST
It was the only SI story Shrake ever wrote that the magazine would not print and Laguerre was embarrassed.
‘The Land of the Permanent Wave’ Is Bud Shrake’s Classic Take on ‘60s Texas|Edwin Shrake|February 2, 2014|DAILY BEAST
With her characteristic fierce energy, Clinton poured herself into the fight, chanting “Si, se puede” at rally after rally.
How Ted Cruz Can Win in 2016|David Frum|October 25, 2013|DAILY BEAST

The SI veteran married singer John Legend in a ceremony in Italy.
Sports Illustrated Swimsuit Model Chrissy Teigen Weds John Legend|Anna Klassen|September 15, 2013|DAILY BEAST
A few days before, Si, while passing near the hospital, saw a weak convalescent faint and fall.
Si Klegg, Book 6 (of 6)|John McElroy
Si sacristia est post altare, a sacristia ad illud e sinistra egrediendum, a dextera ad illam accedendum.
The Irish Ecclesiastical Record, Volume 1, January 1865|Various
Si studiorum quam scortorum nostri episcopi amantiores essent.
History of the Great Reformation, Volume IV|J. H. Merle D'Aubign
Q, all full of eager questions as to their kindred, and this relieved Shorty, for he could tell them quite as well as Si.
Si Klegg, Book 4 (of 6)|John McElroy
The saying of Madame de Sévigné, 'Il faut être, si l'on veut paraître,' is applicable to the reader.
The Voice and Spiritual Education|Hiram Corson

British Dictionary definitions for si (1 of 5)

si¹

/ (siː) /

noun

music a variant of te

British Dictionary definitions for si (2 of 5)

si²

the internet domain name for

Slovenia

British Dictionary definitions for si (3 of 5)

Si¹

Si Kiang

/ (ʃiː) /

noun

a variant transliteration of the Chinese name for the Xi

British Dictionary definitions for si (4 of 5)

Si²

the chemical symbol for

silicon

British Dictionary definitions for si (5 of 5)

symbol for

Système International (d'Unités)See SI unit

abbreviation for

NZ South Island

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for si (1 of 2)

The symbol for the elementsilicon

Medical definitions for si (2 of 2)

abbr.

Système International (d'Unités) (International System of Units)

Scientific definitions for si (1 of 2)

The symbol for silicon.

Scientific definitions for si (2 of 2)

silicon

[ sĭl′ĭ-kŏn′ ]

Si

A metalloid element that occurs in both gray crystalline and brown noncrystalline forms. It is the second most abundant element in the Earth's crust and can be found only in silica and silicates. Silicon is used in glass, semiconductors, concrete, and ceramics. Atomic number 14; atomic weight 28.086; melting point 1,410°C; boiling point 2,355°C; specific gravity 2.33; valence 4. See Periodic Table.