sinus
[ sahy-nuhs ]
/ ˈsaɪ nəs /
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noun, plural si·nus·es.
a curve; bend.
a curving part or recess.
Anatomy.
- any of various cavities, recesses, or passages, as a hollow in a bone, or a reservoir or channel for venous blood.
- one of the hollow cavities in the skull connecting with the nasal cavities.
- an expanded area in a canal or tube.
Pathology. a narrow passage leading to an abscess or the like.
Botany. a small, rounded depression between two projecting lobes, as of a leaf.
QUIZZES
QUIZ YOURSELF ON PARENTHESES AND BRACKETS APLENTY!
Set some time apart to test your bracket symbol knowledge, and see if you can keep your parentheses, squares, curlies, and angles all straight!
Question 1 of 7
Let’s start with some etymology: What are the origins of the typographical word “bracket”?
First appeared around 1750, and is related to the French word “braguette” for the name of codpiece armor.
First appeared in 1610, based on the French word “baguette” for the long loaf of bread.
First appeared in 1555, and is related to the French word “raquette” for a netted bat.
TAKE THE QUIZ TO FIND OUT Origin of sinus
1590–1600; <Latin sinus (stem sinu-) bent or curved surface, curve, fold
OTHER WORDS FROM sinus
si·nus·like, adjectiveWords nearby sinus
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2021
Example sentences from the Web for sinus
British Dictionary definitions for sinus
sinus
/ (ˈsaɪnəs) /
noun plural -nuses
anatomy
- any bodily cavity or hollow space
- a large channel for venous blood, esp between the brain and the skull
- any of the air cavities in the cranial bones
pathol a passage leading to a cavity containing pus
botany a small rounded notch between two lobes of a leaf, petal, etc
an irregularly shaped cavity
Word Origin for sinus
C16: from Latin: a curve, bay
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 sinus
sinus
[ sī′nəs ]
n.
A depression or cavity formed by a bending or curving.
A channel for the passage of blood or lymph, without the coats of an ordinary vessel, such as the blood passages in the gravid uterus or in the cerebral meninges.
Any of various air-filled cavities in the bones of the skull, especially one communicating with the nostrils.
A dilatation in a blood vessel.
A fistula or tract leading to a pus-filled cavity.
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Scientific definitions for sinus
sinus
[ sī′nəs ]
A cavity or hollow space in a bone of the skull, especially one that connects with the nose.
A channel for the passage of a body fluid, such as blood.
The American Heritage® Science Dictionary
Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.