The side of a building which is topped by a gable(noun)
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Use "gable end" in a sentence
"It was not the hope of reaching the village which set my heart singing with joy, but it was that I knew my ground now, and that farm-house not half a mile ahead, with its gable end sticking out from amid the trees, must be that very farm of St. Aunay where we had bivouacked, and which I had named to Captain Sabbatier as the rendezvous of the Hussars of Conflans."