The kanji 彗 generally represents a celestial body with a luminous tail, specifically a comet. It conveys the idea of something that appears suddenly in the sky and then moves or disappears. It implies an appearance, movement, and a transient nature.

・On-yomi (音読み): スイ (sui) ・Kun-yomi (訓読み): なし (nashi) (archaic, used in the word 彗星 (suisei))

⚫︎彗星 (suisei) Translation: Comet ⚫︎彗星のごとく現れる (suisei no gotoku arawareru) Translation: To appear like a comet (suddenly and dramatically) ⚫︎彗眼 (suigan) Translation: A keen eye; a discerning eye (rare usage, but can refer to someone with keen insight)

The kanji 彗 is a phono-semantic compound (形声文字, keisei moji). The semantic component (meaning part) is 彡 (san: hair, or rays) and the phonetic component (sound part) is 彗 (sui). The 彡 part visually suggests the tail of a comet. The whole character indicates an object with a tail, hence a comet.