say it: SAWL-stis
solstice is a noun meaning "either of the two times of the year when the sun is at its greatest distance from the celestial equator". It is pronounced /ˈsɔlstɪs/ — SAWL-stis. It carries one recorded sense.
either of the two times of the year when the sun is at its greatest distance from the celestial equator
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for solstice come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.