One of the two points in the ecliptic at which the sun is furthest from the celestial equator. This corresponds to one of two days in the year when the day is either longest or shortest.

plural of solstice

plural of winter solstice

plural of summer solstice

(astronomy) The moment when the Earth is in that point of its orbit where the northern or southern hemisphere is most inclined toward the sun.

(astronomy) The moment when the Earth is in that point of its orbit where the northern or southern hemisphere is most inclined away from the sun.

A pagan holiday and Wiccan Sabbat

June solstice, when the sun reaches the northernmost point of the sky.

December solstice, when the sun reaches the southernmost point of the sky

(astronomy) The moment when the sun reaches the northernmost point of the sky, occurring on June 20–22. That would be summer solstice in the northern hemisphere and winter solstice in the southern hemisphere.