respiration /res-pər-āˈshən/ noun

1. Breathing
2. The taking in of oxygen and giving out of carbon dioxide, with associated physiological processes
3. A breath
4. A breathing space

resˈpirātor noun

1. An appliance which provides artificial respiration (medicine)
2. An appliance worn on the mouth or nose to filter or warm the air breathed
3. A gas mask

respiratory /resˈpər-ə-tər-i, ri-spīˈrə-tər-i or -spiˈ/ adjective

Of, relating to, or serving for, respiration

respiromˈeter noun

An apparatus for measuring breathing

respiratory quotient noun

The ratio of molecules of carbon dioxide exhaled to molecules of oxygen absorbed in the process of respiration