breather

n. 1. One who breathes. Hence: (a) One who lives. (b) One who utters. (c) One who animates or inspires. [ 1913 Webster ]

2. That which puts one out of breath, as violent exercise. [ Colloq. ] [ 1913 Webster ]

3. a pause to catch one's breath, or for some other form of rest or refreshment; -- often used in the phrase
to take a breather, i.e. to pause for refreshment. [ Colloq. ] [ PJC ]

4. a vent in a container to allow equalization of internal and external pressure. [ PJC ]

5. an air intake pipe to provide air to machinery or people submerged or otherwise sealed off from the outside. [ PJC ]