breather

Short definition from Wiktionary

Noun

1. 1
   Something or someone that breathes.
2. 2
   A heavy breather.
3. 3
   A short break; a rest or respite.
4. 4
   A spatially localized, time-periodic excitation in a one-dimensional lattice.
5. 5
   That which puts one out of breath, such as violent exercise.
6. 6
   An air inlet path to the crankcase