solstice

noun
sol*stice \ ˈsäl-stəs \ ˈsōl- \ ˈsȯl- \
14th century{ds||1||}
  • either of the two points on the ecliptic at which its distance from the celestial equator is greatest and which is reached by the sun each year about June 21 and December 21
  • the time of the sun's passing a solstice which occurs about June 21 to begin summer in the northern hemisphere and about December 21 to begin winter in the northern hemisphere
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