This causes the epithelium of the lower esophagus to constantly renew, and when it's replaced by columnar epithelium, that's called Barrett's esophagus.
Holographic data-storage devices, unlike their refrigerator-size ancestors, looked more like sleek stereo components, each perched atop a columnar pedestal.
In chronic laryngitis the normal columnar cells undergo dysplasia, which is when they transform into squamous epithelium to adapt to the chronic irritation.