Quick answer
沸 is the kanji for "Boil". A common reading is わ.く (waku). You can also practice writing it on this page.
Meaning
Boil
Also : Ferment · Bubble · Uproar
Learn 沸 with SRS
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Readings
kun = Japanese reading · on = Chinese reading
Practice writing
Trace the kanji stroke by stroke with a visual guide.
Stroke Order
8 strokes
Radicals
Memory Aid
The kanji 沸 represents 'SEETHE'. Think of this shape as a picture representing the concept of seethe.
On-reading: ふつ — remember this sound by associating it with seethe. Kun-reading: わ.く.
Example Sentences
お湯が沸いたら、すぐ火を止めてください。
おゆがわいたら、すぐひをとめてください。
Once the water boils, please turn off the heat immediately.
観客席が興奮で沸き立ちました。
かんきゃくせきがこうふんでわきたちました。
The audience seats were abuzz with excitement.
Vocabulary using 沸
Grammar to study at this level
- [Noun] + に伴い～に伴い (ni tomonai) - Along with / In accordance with
- [Noun] + をはじめ～をはじめ (wo hajime) - Starting with / Including
- [Noun] + に応じて～に応じて (ni oujite) - According to / In response to
- [Noun] + から + [Noun] + にかけて～にかけて (ni kakete) - From...to / In the area of
- [Noun] + に限り～に限り (ni kagiri) - Limited to / Only
Last updated Jun 11, 2026
Learn 沸 with Spaced Repetition
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