barn

UK: /ˈbɑː^rn/ US: /bɑrn/ ,(bärn)

WordReference Random House Learner's Dictionary of American English © 2026

barn¹ /bɑrn/   n. [countable]

1. a building for storing hay and grain, and often for keeping animals.

WordReference Random House Unabridged Dictionary of American English © 2026

barn¹  (bärn), n. 

1. a building for storing hay, grain, etc., and often for housing livestock.
2. a very large garage for buses, trucks, etc.;
   carbarn.

v.t. 

3. to store (hay, grain, etc.) in a barn.

• bef. 950; Middle English bern, Old English berern (bere (see barley¹) + ern, ǣrn house, cognate with Old Frisian fīaern cowhouse, Old High German erin, Gothic razn, Old Norse rann house; compare ransack, rest¹)

barn′like′, adj. 

barn²  (bärn), n. [Physics.]

1. Physics a unit of nuclear cross section, equal to 10^-24 square centimeter. Abbr.: b

• special use of barn¹ 1945–50

Collins Concise English Dictionary © HarperCollins Publishers::

barn / bɑːn/ noun

1. a large farm outbuilding, used chiefly for storing hay, grain, etc, but also for housing livestock
2. a large shed for sheltering railroad cars, trucks, etc
3. any large building, esp an unattractive one
4. (modifier) relating to a system of poultry farming in which birds are allowed to move freely within a barn: barn eggs

Etymology: Old English beren, from bere barley + ærn room; see barley¹

barn / bɑːn/ noun

1. a unit of nuclear cross section equal to 10^–28 square metre
   Symbol: b

Etymology: 20th Century: from barn¹; so called because of the relatively large cross section