Breathe

verb

1. To draw air into (inhale), and expel air from (exhale), the lungs in order to extract oxygen and excrete waste gases.
2. To take in needed gases and expel waste gases in a similar way.

   "Fish have gills so they can breathe underwater."

3. To inhale (a gas) to sustain life.

   "While life as we know it depends on oxygen, scientists have speculated that alien life forms might breathe chlorine or methane."

4. To live.

   "I will not allow it, as long as I still breathe."

5. To draw something into the lungs.

   "Try not to breathe too much smoke."