A temple or portico with eight columns in front.(adjective)
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Use "octostyle" in a sentence
"It was, moreover, immeasurably superior to the classic attempts of the architects of the middle Georgian period, who, carried away by the enthusiasm awakened by the perusal of the newly-published "Antiquities" of Stuart and Revett, attempted to adapt Doric porticos, hexastyle, octostyle, etc., to modern domestic architecture."
"It was a peripteral octostyle, of the Doric order, with seventeen columns on the sides, each six feet two inches in diameter at the base, and thirty-four feet in height, elevated on three steps."