- barn - an outlying farm building for storing grain or animal feed and housing farm animals
--1 is a kind of farm building
--1 has particulars: cowbarn, cowshed, cow barn, cowhouse; tithe barn- barn, b - (physics) a unit of nuclear cross section; the effective circular area that one particle presents to another as a target for an encounter
--2 is a kind of area unit, square measure
- barn, b - (physics) a unit of nuclear cross section; the effective circular area that one particle presents to another as a target for an encounter