Decan
A decan is a ten-degree third of a zodiac sign, giving thirty six in all, each with a sub-ruler that tints the meaning of the sign.
Early, middle and late degrees of one sign therefore read a little differently. The Chaldean order assigns the sub-rulers, and our reports print the decan and its ruler beside a planet's position.
Decan and face describe the same ten degrees: decan is the division, face is the dignity a planet gains by ruling it.
Frequently asked
Are decans the same in every tradition?
The division is, but the rulers are not: the Chaldean order and the triplicity order assign them differently.
Do decans change my sign?
No. They add detail within the sign rather than moving a planet out of it.