梅干し
うめぼし · umeboshi · JLPT N1 · noun
plum
梅 (ume, plum) + 干し (boshi, dried) = dried plum
The 干し part comes from the verb 干す (hosu, to dry out), and the rendaku voicing turns hi into bo. It names the salty, sour pickled plum eaten with rice.
干 — pictograph of a forked weapon/shield
干 originally depicted a forked wooden weapon or shield used in ancient warfare, giving the early sense of 'to offend' or 'to oppose.' Over time it took on extended meanings like 'to concern' and 'trunk/stem.' In modern simplified Chinese it also absorbed 乾 (dry) and 幹 (to do; trunk), so one character now covers several unrelated words.