Meaning
雲 means cloud. In everyday Japanese, くも covers all cloud types — from high, wispy cirrus to dark, low-hanging storm clouds. The character appears in weather vocabulary, nature writing, and figurative expressions alike.
The structure tells the story. 雲 combines two parts: the top half is 雨 (rain), and the lower half is 云, an ancient character originally drawn as the curling curves of clouds. Oracle bone inscriptions show 云 as a simple swirling form. Once 雨 was placed above it, the new character 雲 linked clouds directly to the rain they carry. Over time, 云 shifted in written Chinese to mean "to say" or "so-called," while 雲 kept its hold on clouds.
雲 has 12 strokes and appears in Grade 2 of Japanese elementary school. Its radical is 雨 (rain), placing it in the same family as 雪 (snow), 雷 (thunder), and 霧 (fog) — all weather kanji built on the same base.
Readings
On'yomi (音読み) — Chinese-derived readings
The on'yomi is ウン (un), drawn from the Middle Chinese pronunciation. It appears mostly in formal vocabulary, meteorological terms, and classical expressions rather than casual speech.
- 雲海 (unkai) — sea of clouds; when mist fills a valley and a mountaintop observer looks out over an ocean of white
- 暗雲 (an'un) — dark clouds; used literally for storm clouds, and figuratively for any looming sense of trouble
- 白雲 (hakuun) — white clouds; a literary term for fair-weather clouds, common in classical verse
- 雲量 (unryō) — cloud cover; the meteorological scale (0–10) measuring how much sky is obscured
Kun'yomi (訓読み) — Native Japanese readings
The kun'yomi is くも (kumo) — the native Japanese word for cloud. This is the reading you hear in daily conversation. When 雲 stands alone as a noun, it is always read this way.
- 雲 (kumo) — cloud
- 雨雲 (amagumo) — rain cloud; a dark, low cloud signaling rain is close
- 入道雲 (nyūdōgumo) — cumulonimbus; the towering summer storm cloud, named for its resemblance to a Buddhist monk's shaved head
- 雲行き (kumoyuki) — literally how the clouds are moving; figuratively, how a situation is developing — usually with a sense that things may go wrong
Common Words & Compounds
雲 shows up across weather vocabulary, nature writing, idioms, and classical literature. Here are key compounds grouped by usage.
Weather and Nature
- 雲 (kumo) — cloud
- 雨雲 (amagumo) — rain cloud
- 積乱雲 (sekiranun) — cumulonimbus; the tall, vertical storm cloud
- 入道雲 (nyūdōgumo) — summer thundercloud; the massive, billowing formation of hot-season storms
- 雲海 (unkai) — sea of clouds; visible from mountaintops when valleys fill with mist
- 雲母 (unmo) — mica; named for its cloud-like, layered shimmer
Figurative and Idiomatic
- 暗雲 (an'un) — dark cloud; a metaphor for trouble ahead
- 雲行き (kumoyuki) — how things are going; used when a situation is uncertain or turning bad
- 雲泥の差 (undei no sa) — a world of difference; literally "the gap between cloud and mud," describing an enormous difference in quality or status
- 雲散霧消 (unsan mushō) — to vanish without a trace; a yojijukugo meaning to disappear like clouds scattering and mist dissolving
Literary and Atmospheric
- 白雲 (hakuun) — white cloud; a classical poetry staple evoking serenity and the passing of time
- 片雲 (hen'un) — a lone cloud; a single cloud drifting in isolation, often used in haiku
- 雲上 (unjō) — above the clouds; both a physical description of high altitude and, in classical usage, a reference to those of noble rank
Example Sentences
空に大きな雲が浮かんでいます。
Sora ni ōkina kumo ga ukande imasu.
Large clouds are floating in the sky.
雨雲が近づいてきたので、傘を持って出かけました。
Amagumo ga chikazuite kita node, kasa wo motte dekakemashita.
Rain clouds were moving in, so I grabbed an umbrella before heading out.
山の上から雲海を見ることができました。
Yama no ue kara unkai wo miru koto ga dekimashita.
From the mountaintop, I could see a sea of clouds stretching below.
夏の入道雲は、とても迫力がある。
Natsu no nyūdōgumo wa, totemo hakuryoku ga aru.
Summer cumulonimbus clouds are genuinely awe-inspiring.
雲の間から太陽が顔を出した。
Kumo no aida kara taiyō ga kao wo dashita.
The sun peeked out from between the clouds.
この会社の雲行きは、最近あまりよくない。
Kono kaisha no kumoyuki wa, saikin amari yokunai.
Things haven't been looking good at this company lately.
二人の実力には雲泥の差がある。
Futari no jitsuryoku ni wa undei no sa ga aru.
There's a world of difference between the two in terms of ability.
夕方になると、雲がオレンジ色に染まった。
Yūgata ni naru to, kumo ga orenji-iro ni somatta.
As evening fell, the clouds turned orange.
彼の不安は雲散霧消した。
Kare no fuan wa unsan mushō shita.
His anxiety vanished without a trace.
暗雲が立ち込める中、試合は始まった。
An'un ga tachikomeru naka, shiai wa hajimatta.
Under gathering dark clouds, the match began.
Memory Tip
Read 雲 as a picture. The top half is 雨 (rain) — a character you likely already know. Below it sits a rounded, swirling shape: the ancient pictograph for billowing clouds. Rain sits on top of cloud. That's the whole story.
Vietnamese learners have an extra hook: the on'yomi ウン corresponds to the Hán-Việt reading VÂN. Think of 白雲 (はくうん, hakuun) as Bạch Vân — White Cloud. The same word root connects both languages through shared Chinese heritage.