What does "sinus" mean?
A pouch or cavity in a bone or other tissue, especially one in the bones of the face or skull connecting with the nasal cavities (the paranasal sinus).
Sinus
/ˈsaɪ.nəs/ noun
noun ·Moderate ·College level
Meaning at a glance
- Primary sense: A pouch or cavity in a bone or other tissue, especially one in the bones of the face or skull connecting with the nasal cavities (the paranasal sinus).
- Grammar: sinus is listed as noun.
- Nearest alternatives: venous sinus, air-filled cavity, alveolation, alveolus.
- Useful contrasts: arterial vessel, artery, solid mass.
- Usage evidence: Sinus infection is a nuisance to most people.
How to use "sinus"
- Start with the primary definition, then check the part of speech before placing the word in a sentence.
- Compare nearby synonyms to make sure "sinus" carries the exact meaning, tone, and strength you need.
- Use the example sentence as a context check. If your sentence uses the word differently, confirm that the grammar still fits.
Meaning check
- Does the word fit the sentence's grammar?
- Does it match the intended tone rather than only the dictionary definition?
- Would a simpler synonym be clearer for the reader?
- Is there enough surrounding context to prevent ambiguity?
Source and review context
This entry combines structured lexical data with WordToolSet review checks. Definitions, examples, synonyms, and usage notes may come from different source tables, so the page is designed to show evidence from more than one angle before you rely on "sinus" in a final draft.
If a word has several senses, prefer the sense that matches your sentence's grammar and surrounding context. A correct definition can still be the wrong choice when the sentence needs a different register, emphasis, or level of specificity.
Before you rely on this definition
Read the first definition as a starting point, then check the example, synonyms, and part of speech before treating "sinus" as the right word for your sentence.
If your draft is formal, technical, persuasive, or sensitive, compare "sinus" with a nearby alternative so the final choice matches both meaning and reader expectation.
Compare nearby meanings
- Use synonyms when you need a softer, stronger, simpler, or more specific word.
- Use antonyms to check the boundary of the meaning and avoid accidental contrast.
- Use the example sentence to confirm the word behaves naturally in context.
- Keep the original wording when a replacement adds complexity without improving precision.
Definition decision workflow
1. Identify the role
Check whether "sinus" is acting as noun in your sentence. A definition is only useful when the grammar matches the way the word is being used.
2. Test the nearest option
Compare it with "venous sinus" and other nearby choices to see whether the sentence needs a softer, stronger, or more familiar word.
3. Confirm with context
Use the example sentence below as an evidence check, then read your own sentence out loud to catch tone or rhythm problems.
Review note: Definition pages are checked for source coverage, sentence evidence, synonym support, and editorial insight before they are treated as approval-ready pages. If the evidence is too thin, the page remains available to users but is kept out of the approval-facing indexed inventory.
Final meaning check
Before publishing a sentence with "sinus", ask whether the word helps the reader understand the idea faster. A precise word should reduce confusion, not simply make the sentence look more polished.
When the definition, synonym evidence, and example context point in the same direction, the word is usually a safer choice. When they conflict, revise the sentence or choose a clearer alternative.
Definitions
Noun
- 1 A pouch or cavity in a bone or other tissue, especially one in the bones of the face or skull connecting with the nasal cavities (the paranasal sinus).
- 2 a wide channel containing blood; does not have the coating of an ordinary blood vessel wordnet
- 3 An irregular venous or lymphatic cavity, reservoir, or dilated vessel.
- 4 any of various air-filled cavities especially in the bones of the skull wordnet
- 5 An irregular venous or lymphatic cavity, reservoir, or dilated vessel.; Relating to or denoting the sinoatrial node of the heart or its function of regulating the heartbeat. attributive
Show 5 more definitions
- 6 an abnormal passage leading from a suppurating cavity to the body surface wordnet
- 7 An abnormal cavity or passage such as a fistula, leading from a deep-seated infection and discharging pus to the surface.
- 8 A rounded notch or depression between two lobes or teeth in the margin of a leaf or petal.
- 9 A bay of the sea; a recess in the shore.
- 10 Synonym of sine.
"So, in the helicopteron, as the helix is at the same time a sustaining plane, it should be likened to a surface moving horizontally, and in which, consequenty, the resistance to motion will be to the lifting power as the sinus is to the cosinus of the angle formed by such plane with the horizon."
Synonyms
All synonymsAntonyms
Example
"Sinus infection is a nuisance to most people."
Common questions
What is a synonym for "sinus"?
Common synonyms include: venous sinus, air-filled cavity, alveolation, alveolus, anatomy, antrum.
How do you use "sinus" in a sentence?
Sinus infection is a nuisance to most people.
How do you pronounce "sinus"?
Pronounced /ˈsaɪ.nəs/.
Etymology
Learned borrowing from Latin sinus (“a bent surface, curve, hollow”). Doublet of sine.