in Architecture, a kind of vestibule supported by columns, and much used at the entrance of temples, halls, and other edifices.

A porch, in ancient architecture, was a vestibule, or a disposition of insulated columns usually crowned with a pediment, forming a covert place before the principal door of a temple or court of justice. When a porch had four columns in front, it was called a tetrastyle; when six, a hexastyle; when eight, an octostyle, and so on.

Poros, in Greek ερως, a public portico in Athens, adorned with the pictures of Polygnotus and other eminent painters. It was in this portico that Zeno the philosopher taught; and hence his followers were called Stoics.