As an astrological term, cardinal is one of the qualities which are associated with a sign of the zodiac.

Traits associated with cardinal signs are an ability to come up with new ideas and courses of action. They are self-starters and may enjoy taking charge of projects. On the down side, this may tend to induce a bit of inflexibility or a "control freak" mentality.

These are named cardinal, because when looking at a wheel of zodiac signs, these signs are at north, south, east, and west -- the cardinal points on a compass.

The qualities: cardinal, fixed, mutable