From Longman Dictionary of Contemporary Englishlean-toˈlean-to noun [countable] TBBBUILDa small roughly-made building that is built against the side of a larger building → shed
Examples from the Corpus
lean-to• I spend three months of every year in a lean-to.• They worked all day in the mud; at night they slept on compacted mud under hessian lean-tos.• Blackbirds have raised a brood in the lean-to where we keep the logs.• When I came back from fishing yesterday you were beside me in the lean-to gutting the catch with me.• After a second helping, Alice took Mungo into the lean-to.• We leaned back against the irregular planks of the lean-to.• We lay on our mattress, propped against the back wall of the lean-to.• Sorted out the test roster and Greg has worked wonders with the lean-to. 