anemia.  A deficiency in the amount or type of hemoglobin in blood.

aspirate.  To suck something into the airways or lungs.  Also used in medicine to mean removed by suction.

atelectasis.  Collapse (or lack of expansion) of a region of the lungs;  lack of air in alveoli.

bends.  Pain in the joints (and sometimes in the abdomen) due to nitrogen bubbles in the blood (nitrogen gas emboli).  Usually caused by a rapid reduction in ambient pressure.  Also called decompression sickness.

bronchitis.  Inflammation of the respiratory airways.

bronchiolitis.  Inflammation of the bronchioles..

COLD.  Chronic Obstructive Lung Disease.

compliance.  Ease of distortion.  In the respiratory system, compliance is the ratio of volume change to pressure change, DV/DP.

COPD.  Chronic Obstructive Pulmonary Disease.   (Same meaning as COLD.)

croup.  Infection of the larynx and/or trachea.

dyspnea.  Sensation of difficulty in breathing.

embolism.  A body in the circulation that obstructs blood flow.  There are a number of types of emboli, including thromboemboli (blood clots in the circulation), fat emboli (due, for example, to release of fat globules into the circulation from bone marrow as can occur in fractures accompanying traumatic accidents), and air emboli (due, for example, to faulty injection technique).

hemoptysis.  Coughing or spitting up blood from the respiratory system.

hypertension.  Increase in arterial pressure above normal.  Hypertension can be either systemic (increase pressure in the aorta and outer large systemic arterteries) or pulmonary (increase in pulmonary artery pressure).   If the hypertension is used without specifying the either systemic or pulmonary, then systemic hypertension is meant.

hypotension.  Decrease in arterial pressure above normal.

hysteresis.  In the respiratory system, the lagging of lung volume changes behind lung pressure changes.

microemboli.  Small emboli

pneumonia.  Lung inflammation and (usually) infection..

polycythemia.  An abnormally large number of red cells (erythrocytes) in the circulation.

respiratory ratio (R).  The ratio of carbon dioxide production to oxygen consumption, V'CO2 / V'O2

shunt.  In respiratory physiology, a passageway for blood to bypass an organ.  In a right-to-left shunt, blood passes from systemic veins to systemic arteries bypassing the pulmonary capillaries (so that it does not exchange oxygen or carbon dioxide with the alveoli).

SIDS.  Sudden Infant Death Syndrome.

surfactant.  A substance that lowers surface tension.   Surfactant produced by lung tissue  is termed "pulmonary surfactant".

volatile.  Evaporating easily at normal temperatures