Imbrex — curved tile designed to fit over the raised flanges of the tegulae, which are the flat, rectangular roof tiles commonly used in Roman construction. The imbrex tile has a concave shape that allows it to interlock with the adjacent tegulae tiles, creating a watertight seal on the roof. Its curved design helps to channel rainwater away from the roof and into the gutters or drainage systems.

Imbrex tiles were typically made of clay or terracotta and were widely used in Roman buildings, including houses, villas, and public structures. They were laid in overlapping rows, with each imbrex tile fitting snugly over the raised edges of the tegulae tiles beneath it.

The use of imbrex tiles in Roman architecture not only served a functional purpose by protecting the structure from water damage but also added an aesthetically pleasing element to the roofline. The distinctive curvature of the imbrex tiles created a visually appealing pattern that enhanced the overall architectural design.