barn barn /ˈbɑːrn/

noun

1. () An outlying farm building for storing grain or animal feed and housing farm animals  ( barn )
   an outlying farm building for storing grain or animal feed and housing farm animals
    The farmer stored hay in the barn to feed his animals during the winter
   The farmer stored hay in the barn to feed his animals during the winter
   
   
2. (physics) a unit of nuclear cross section; the effective circular area that one particle presents to another as a target for an encounter  ( b , barn )
   (physics) a unit of nuclear cross section; the effective circular area that one particle presents to another as a target for an encounter