Respiratory System Word Search

Print 16 respiratory system words with an answer key, or follow the airway from nostril to alveoli.

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0 of 16 words found

BESLUNGSIHSTBMP

RXIMYDIFFUSIONL

AHFIRATWSHDCBOE

LANYRRHDTIIERUU

ZLVHYMRFISATOOR

BEGBWINDPIPENRA

RUPGSEDAICHICMT

EIWHTFTIHIROHOR

AYSOCAPILLARIES

THORAXHCOIGIEGD

HNUGYWADBAMUCUS

ECOUGHRJEELZDME

HUAHPMYTOKTDGOD

ZEWTWFNOSTRILLK

SFYWKWXHDNHMHSI

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NostrilNOSTRIL
CiliaCILIA
MucusMUCUS
PharynxPHARYNX
WindpipeWINDPIPE
LungsLUNGS
LobeLOBE
PleuraPLEURA
BronchiBRONCHI
DiaphragmDIAPHRAGM
ThoraxTHORAX
ExhaleEXHALE
BreatheBREATHE
CoughCOUGH
DiffusionDIFFUSION
CapillariesCAPILLARIES

16 of 23 words from the Respiratory System Key Terms list.

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Answer key: Respiratory System Word Search

BESLUNGSIHSTBMP

RXIMYDIFFUSIONL

AHFIRATWSHDCBOE

LANYRRHDTIIERUU

ZLVHYMRFISATOOR

BEGBWINDPIPENRA

RUPGSEDAICHICMT

EIWHTFTIHIROHOR

AYSOCAPILLARIES

THORAXHCOIGIEGD

HNUGYWADBAMUCUS

ECOUGHRJEELZDME

HUAHPMYTOKTDGOD

ZEWTWFNOSTRILLK

SFYWKWXHDNHMHSI

NOSTRIL, CILIA, MUCUS, PHARYNX, WINDPIPE, LUNGS, LOBE, PLEURA, BRONCHI, DIAPHRAGM, THORAX, EXHALE, BREATHE, COUGH, DIFFUSION, CAPILLARIES

Next step Type in the terms from your own respiratory chapter Scramble the same breathing words

All 85 words

Parts of the Airway 20

Air The mix of gases that travels down the airway: mostly nitrogen, about a fifth oxygen.
Alveolar duct A tiny passage near the end of the airway whose walls are lined with air sacs.
Alveoli Millions of tiny, cup-shaped air sacs in the lungs where gas exchange takes place.
Bronchiole A smaller branch of the airway inside a lung, with no cartilage in its wall.
Bronchus One of the two main tubes that branch from the trachea, one into each lung.
Carina The ridge of cartilage at the base of the trachea, between the two main bronchi.
Cilia Tiny hair-like parts on the cells that line the airway; they sweep mucus along.
Conchae Long, curled shelves of bone that stick out into the breathing passage of the nose.
Epiglottis The leaf-shaped flap that closes during swallowing to keep food out of the trachea.
Larynx The organ at the top of the neck that houses the vocal cords.
Mucus The slippery gel that lines the airway and traps breathed-in particles.
Nasal cavity The air-filled space above and behind the nose, split in two by the septum.
Nostril Either of the two openings of the nose, where air goes in and out.

Show all 85 words (72 more)

Parts of the Airway, continued

Pharynx The part of the throat behind the mouth and nasal cavity; it carries both air and food.
Sinus One of the four pairs of air-filled spaces that surround the nasal cavity.
Throat The front part of the neck; it contains the pharynx and the larynx.
Trachea The tube, stiffened with cartilage, running from the larynx to the bronchi.
Vocal folds Folds of tissue in the larynx that vibrate to make sound; open during breathing.
Voice box The common name for the larynx.
Windpipe The everyday name for the trachea.

Lungs and Chest 18

Apex The narrow, rounded top of a lung.
Base The broad bottom of a lung, which rests on the diaphragm.
Bronchi The tubes that carry air into the lungs; the two widest branch from the trachea.
Cardiac notch The dent in the border of the left lung that makes room for the heart.
Chest wall The ribs and muscles around the lungs; the pleura separates each lung from it.
Diaphragm The sheet of muscle across the bottom of the chest: the most important breathing muscle.
Elastic Able to stretch and spring back, like the fibers in lung tissue.
Fissure A deep groove that divides a lung into lobes.
Hilum The dip in each lung where the airways and blood vessels pass in.
Intercostal Describes the muscles that run between the ribs and help move the chest wall.
Lobe A section of a lung: the right lung has three and the left has two.
Lungs The two organs in the chest, one on each side of the heart, that take in air.
Mediastinum The central compartment of the chest, which holds the heart, between the lungs.
Pleura The fluid-filled sac of thin membrane that surrounds each lung.
Pulmonary Having to do with the lungs.
Rib cage The frame of ribs, backbone and breastbone that protects the heart and lungs.
Surfactant A mix of fats and proteins, made by cells of the alveoli, in the fluid that lines them.
Thorax The chest: the part of the body between the neck and the abdomen.

How Breathing Works 27

Airflow The movement of air through the breathing passages.
Brainstem The part of the brain whose centers control the rate and depth of breathing.
Breathe To move air into the lungs and out again.
Cough A sudden push of air through the large breathing passages that helps clear them.
Exhalation Breathing out: the diaphragm relaxes and air flows from the lungs.
Exhale To breathe out.
Expand To get bigger; the lungs do this only when the chest cavity grows.
Gasp To draw in breath sharply.
Glottis The part of the larynx with the opening between the vocal cords; it shuts in a hiccup.
Hiccup A jerk of the diaphragm you cannot control, followed by the glottis snapping shut.
Inhalation Breathing in: air enters the lungs as the chest gets bigger.
Inhale To breathe in.
Medulla The lower part of the brainstem; it holds part of the center that controls breathing.
Pant To breathe quickly; animals that cannot sweat much do it to cool down.
Rate How fast breathing happens, usually counted in breaths per minute.
Recoil The springing back of stretched lungs and chest wall that pushes air out at rest.
Rhythm The steady in-and-out pattern of breathing.
Sigh A deep, long breath in and out that can be heard, as when tired or relieved.
Sneeze A sudden burst of air from the lungs through the nose and mouth.
Sniff To draw air in through the nose in short, quick breaths.
Snore To make a rough sound in sleep as air squeezes past a partly blocked upper airway.
Spirometer A device that measures the volume of air breathed in and out of the lungs.
Tidal volume How much air is breathed in and out with each breath.
Ventilation The movement of air into and out of the lungs; a spirometer measures it.
Vital capacity The most air a person can push out of the lungs after the deepest breath in.
Voice The sound made when the vocal folds vibrate.
Yawn A reflex: a long breath in with the mouth opening wide, then a quick breath out.

Gas Exchange 20

Altitude Height above sea level; higher up, more air must be breathed for the same oxygen.
Argon One of the gases found in small amounts in the air we breathe in.
Barrier The blood-air one is the thin wall between the air in an alveolus and the blood.
Bicarbonate The form in which most carbon dioxide is carried in the blood.
Bloodstream The blood flowing around the body, carrying gases to and from the lungs.
Capillaries The smallest blood vessels in the body; gases pass through their thin walls.
Carbon dioxide The gas that leaves the blood in the lungs; breathed-out air is 4 to 5 percent this.
Circulation The movement of blood around the body; the pulmonary loop runs through the lungs.
Diffusion Movement from where there is more of something to where there is less.
Exchange A swap; in the alveoli oxygen is swapped for carbon dioxide.
Glucose A sugar; cells break it down as fuel.
Gradient A difference in concentration from one place to another; diffusion runs down it.
Membrane A very thin layer; gases can move across one by diffusion.
Mitochondria The parts of a cell that use oxygen to make its energy supply.
Nitrogen The gas that makes up 78 percent of the air we breathe in.
Oxygen The gas the body takes from air; it makes up about 21 percent of what we breathe in.
Red blood cell The most common kind in blood, and the body's main way of delivering oxygen.
Respiration In cells, the process that uses oxygen to release energy from fuel such as glucose.
Waste Something the body must get rid of, as carbon dioxide is.
Water vapor Water as a gas; air is warmed and filled with it on the way through the nose.

How this list was compiled: Own work: the word list and every clue were written for this page. The facts in the clues were checked on 2026-10-08 against English Wikipedia (CC BY-SA 4.0), among them the articles on the respiratory system (https://en.wikipedia.org/wiki/Respiratory_system), the lung (https://en.wikipedia.org/wiki/Lung), breathing (https://en.wikipedia.org/wiki/Breathing), the trachea (https://en.wikipedia.org/wiki/Trachea) and the pulmonary alveolus (https://en.wikipedia.org/wiki/Pulmonary_alveolus), and plain word meanings against Wiktionary (https://en.wiktionary.org/). A vocabulary list for class, not medical advice. Licence: own work

How it works

This respiratory system word search has a list for each part of the job: the airway, part by part; the lungs and chest around it; how breathing works; and the gas exchange at the end of the trip.

Read the full guide

The airway, in the order air travels

Pick Parts of the Airway under Start from a list. Taken in the order air travels, its 20 words run from Nostril, Nasal cavity and Pharynx past Epiglottis, Larynx and Trachea to Bronchus, Bronchiole and Alveoli. Where a part has two names, both are there: Larynx and Voice box, Trachea and Windpipe.

A respiratory word search for older classes

Gas Exchange has 20 words, such as Diffusion, Capillaries, Bicarbonate and Mitochondria. Lungs and Chest has 18, with Pleura, Hilum, Surfactant and Mediastinum. How Breathing Works has 27, from Inhale and Exhale to Tidal volume, Hiccup and Yawn. Hard Respiratory System collects 37 words of 8 to 13 letters.

Bronchi reads inside Bronchiole, so the airway list has Bronchus, and Bronchi sits in Lungs and Chest.
Carbon dioxide, Red blood cell and Vital capacity each hide as one run of letters: REDBLOODCELL.

Questions and answers

What is the path of air through the respiratory system?

In through the nostrils to the nasal cavity, down the pharynx and the larynx, through the trachea into the two main bronchi, then along narrower bronchi and bronchioles to the alveoli, the tiny air sacs where gas exchange takes place.

What is the main muscle used in breathing?

The diaphragm, a sheet of muscle across the bottom of the chest cavity. The intercostal muscles, which run between the ribs, help by making the chest cavity bigger and smaller.

How many lobes do the lungs have?

Five. Three lobes make up the right lung and two the left. The left lung shares its space with the heart and has a dent in its border, the cardiac notch, to make room.

What happens in the alveoli?

Gas exchange. Oxygen passes from the air in each sac into the blood of the capillaries wrapped around it, and carbon dioxide passes the other way. A normal pair of human lungs has about 480 million alveoli.

Does the respiratory system word search have an answer key?

Yes, it prints after the puzzle on Letter or A4. With Show clues, not words ticked, Epiglottis prints as "The leaf-shaped flap that closes during swallowing to keep food out of the trachea."

All 85 words

Parts of the Airway 20

Parts of the Airway, continued

Lungs and Chest 18

How Breathing Works 27

Gas Exchange 20

How it works

The airway, in the order air travels

A respiratory word search for older classes

Questions and answers

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