直流
ちょくりゅう · chokuryuu · JLPT N2 · noun
direct current
🔋 直 (straight) + 流 (flow): current that flows straight in one direction only
直 means straight and 流 means flow. Direct current keeps moving one way, unlike 交流 (kouryuu), alternating current, which keeps reversing direction.
直 — 十 ten + 目 eye + 乚 hidden line
Originally depicted an eye (目) looking straight along a vertical line, suggesting a direct, unswerving gaze. The form combines 目 'eye' with strokes indicating straightness. From this came the meanings 'straight,' 'upright,' and by extension 'honest' or 'direct.'
流 — water radical 氵 + 㐬 (phonetic, child being born)
流 is a semantic-phonetic compound. The water radical 氵 gives the meaning, while 㐬 depicts an infant being born head-down with amniotic fluid, suggesting downward flow. Together they convey water flowing, and by extension 'to flow' or 'current'.