n. 1. Either of the two times each year when the sun is furthest from the equator
2. A stopping or turning point, or a culmination of something.
Comes from Latin solstitium, from sol ‘sun’ + sistere ‘to stand still.’ This is because, even though the sun clearly continues to rise and set, its course appears to gradually move across the sky between the spring and autumn equinoxes (remember that word?), and then back again, while at the solstices its course stops before beginning to move the other direction.
Marks the first day of summer, (the summer solstice, which is the longest day of the year) and the first day of winter (winter solstice, shortest day).
The same root gives us armistice (a ‘standing still’ of arms, or weapons) and assist, literally ‘helping to stand.’