水星 すいせい Meanings Noun Mercury (planet) Kanji 水 water. Read as スイ. 星 star. Read as セイ. Example sentences 水星は太陽に一番近い惑星です。Mercury is the planet nearest to the sun. 水星は太陽に一番近い惑星なのに、金星のほうがもっと暑い。Despite Mercury being the closest planet to the Sun, Venus is hotter. Word lists Astronomy Written Jinuma: Japanese Dictionary · Word lists