nostril

American  

[nos-truhl] / ˈnɒs trəl /

noun

1. either of the two external openings of the nose.

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nostril British  

/ ˈnɒstrɪl /

noun

1. either of the two external openings of the nose

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Etymology

Origin of nostril

before 1000; Middle English nostrill, Old English nosterl, variant of nosthyrl, equivalent to nos ( u ) nose + thyrel hole; see thirl

Explanation

A nostril is one of the two holes in your nose through which you breathe, smell, and (sometimes) sneeze. Try not to get anything stuck in your nostrils; they're important passageways! Your nostrils are extremely important, since they provide a direct connection to your lungs — for air — and your olfactory nerves, which your body uses to smell things. You are almost certainly aware of your two external nostrils, but you may not know that you've got two more, inside your head at the very back of the nasal cavity. Most animals have nostrils, even fish — though they use theirs only for smelling, not for breathing. Fittingly, the Old English source of nostril, nosðirl, translates to "the hole of the nose."

Example Sentences

This one performed the same series of tests: A camera went into my nostril.

From Slate • Apr. 18, 2026

I also do breathing exercises, like alternate nostril breathing and straw breathing, where you breathe in through your nose and out through a small hole in your mouth as if you have a straw there.

From Los Angeles Times • Aug. 28, 2025

Dressed in a dark suit and blue tie, Rossi was seated in a wheelchair and had an oxygen tube in his nostril as the proceedings got under way.

From BBC • Aug. 11, 2025

They introduced these virus suspensions drop-by-drop into each nostril of the piglets and monitored them for 5 days to see whether they displayed any symptoms, including changes in body temperature.

From Science Daily • Mar. 18, 2024

Then with her other hand she shined a flashlight up the nostril.

From "Dead End in Norvelt" by Jack Gantos