equinox
/ˈiːkwɪˌnɒks/
[C] Countable
pl: equinoxes
This term describes a precise astronomical moment of balance. It carries a connotation of symmetry and transition, serving as a cosmic pivot point between the expanding light of summer and the encroaching darkness of winter. While "solstice" refers to the extremes of the solar cycle (longest or shortest day), "equinox" represents the exact midpoint. It is used primarily in scientific, astrological, or seasonal contexts to mark a change in the earth's tilt relative to the sun.
Used to refer to the specific occurrences in the yearly cycle, such as the two distinct equinoxes that happen every year.