This shows grade level based on the word's complexity.
si
[ see ]
/ si /
Save This Word!
This shows grade level based on the word's complexity.
noun Music.
the syllable used for the seventh tone of a scale and sometimes for the tone B.
QUIZ
WILL YOU SAIL OR STUMBLE ON THESE GRAMMAR QUESTIONS?
Smoothly step over to these common grammar mistakes that trip many people up. Good luck!
Question 1 of 7
Fill in the blank: I can’t figure out _____ gave me this gift.
Origin of si
First recorded in 1720–30; see origin at gamut
Words nearby si
shy away from, Shylock, Shymkent, shypoo, shyster, si, siabon, Siad Barre, sial, sialadenitis, sialagogic
Other definitions for si (2 of 4)
Si
Symbol, Chemistry.
silicon.
Other definitions for si (3 of 4)
Other definitions for si (4 of 4)
S.I.
abbreviation
Sandwich Islands.
Staten Island.
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
How to use si in a sentence
British Dictionary definitions for si (1 of 5)
British Dictionary definitions for si (2 of 5)
si2
the internet domain name for
Slovenia
British Dictionary definitions for si (3 of 5)
British Dictionary definitions for si (4 of 5)
Si2
the chemical symbol for
silicon
British Dictionary definitions for si (5 of 5)
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
Scientific definitions for si
Si
The symbol for silicon.
The American Heritage® Science Dictionary
Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.