Tropical zodiac
In plain words
The zodiac measured from the first day of spring. Its signs are seasons, and it is what Western astrology has used since Ptolemy. This is what the Oracle uses unless you change it.
In the tradition's terms
Ecliptic longitude measured from the vernal equinox — a zodiac of seasons rather than of stars.
In depth
Zero Aries is the equinoctial point, so the frame precesses with it. Fixed relative to the seasons, drifting relative to the constellations at about 50 arcseconds a year.