航海
háng hǎi · HSK 7
voyage by sea
⛵🧭 航 = boat/vessel + 海 = sea, so navigating boats across the sea
航 carries the boat radical 舟 and means to sail or fly a craft; 海 is sea. Together they mean voyaging by sea, sailing, or navigation. The 舟 element on the left flags anything boat-related.
海 — water radical 氵 + 每 (phonetic)
海 is a phono-semantic compound. The 氵 (water) radical signals the meaning—a vast body of water—while 每 supplies the sound. Originally referring to the sea or ocean, it later extended figuratively to mean 'vast' or 'a great quantity,' as in 人海 (a sea of people).