Face
A face is the ten-degree division of a sign in the dignity scheme, ruled in the Chaldean order, and it is the weakest of the five essential dignities.
The three faces of a sign line up with its three decans, so the two words describe the same ten degrees from different angles: decan is the division, face is the dignity a planet gains by standing in the division it rules.
Classical writers describe a planet in its own face as being at the door of its own house: recognisable, but with little authority.
Frequently asked
Is a face the same as a decan?
They cover the same ten degrees. Decan names the division; face names the dignity a planet has when it rules that division.
How weak is face dignity?
It is the lowest tier, enough to keep a planet from being called peregrine and rarely enough to decide anything on its own.