A sextile is an aspect centered on 60°, one sixth of a circle. Near-exact separations qualify only under the chart’s declared orb policy.
Astrology commonly interprets a sextile as an opening, cooperation, or possibility that benefits from participation. That language is symbolic and should not be turned into a promised opportunity or event.
The angular distance is calculated; the target list, orb, and meaning are conventions. A sextile is half the angular size of a trine, but the two should not be treated as interchangeable labels.