: noninvasive visualization of the interior of the colon by means of computed tomography or magnetic resonance imaging especially to screen for polyps or cancerous growths
: noninvasive visualization of the interior of the colon by means of computed tomography or magnetic resonance imagingespecially: ct colonographyA colonography, also known as a "virtual colonoscopy," uses a very high-powered CAT scan to reconstruct what the colon looks like. — Debbie Blank, The Herald Tribune (Batesville, Indiana), 18 Mar. 2011