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sinusitis

American  
[sahy-nuh-sahy-tis] / ˌsaɪ nəˈsaɪ tɪs /

noun

Pathology.
  1. inflammation of a sinus or the sinuses.


sinusitis British  
/ ˌsaɪnəˈsaɪtɪs /

noun

  1. inflammation of the membrane lining a sinus, esp a nasal sinus

"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

Etymology

Origin of sinusitis

From New Latin, dating back to 1900–05; see origin at sinus, -itis

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Antibiotic use is driven largely by common colds, which produce secondary bacterial things like sore throat, earache, nasal congestion, sinusitis.

From Slate • Oct. 8, 2025

Hosting him will be King Charles and a full line-up of senior royals, currently including Queen Camilla, who had to miss the Duchess of Kent's funeral on Tuesday because she was suffering from acute sinusitis.

From BBC • Sep. 16, 2025

Although over-the-counter nasal sprays offer marginal relief, no FDA-approved medication exists for the most common form of the condition, chronic rhinosinusitis without nasal polyps, known as "chronic sinusitis."

From Science Daily • Jan. 18, 2024

Their youngest son, James, also was diagnosed with pneumonia, while Silva and their other son, Alexander, struggled with sinusitis and ear infections.

From Los Angeles Times • Feb. 21, 2023

His most troubling conditions were a strangely recurrent viral pneumonia, chronic sinusitis, and the ulcerative colitis that had laid him low the weekend before his scheduled testimony against Oppenheimer.

From "Big Science" by Michael Hiltzik