Longman Dictionary of Contemporary English homepage

Date: 1400-1500
Language: Modern Latin
Origin: Latin, 'curve, fold, hollow place'

sinus

noun
     
Related topics: Human
siā€§nus [countable]
HBH your sinuses are the spaces in the bones of your head that are connected to the inside of your nose:
blocked sinuses
a sinus infection

Dictionary pictures of the day
Do you know what each of these is called?
What is the word for picture 1? What is the word for picture 2? What is the word for picture 3? What is the word for picture 4?
Click on any of the pictures above to find out what it is called.

Explore our topic dictionary