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膨張 (ぼうちょう) Japanese meaning | Kotomora
Common word JLPT N1 Freq. Frequency Top 20,000 Conjugation Meanings 1
noun, noun or participle which takes 'suru', intransitive verb
expansion ; swelling ; increase ; growth
Covers physical expansion (gas, metal), swelling (body parts, materials), and abstract growth (budget, scale, population). Often used with する to mean 'to expand' or 'to swell'.
The budget has ballooned.
Written forms 膨ぼう 張ちょう Usage 92%
Standard modern spelling. Preferred in news and general use.
膨ぼう 脹ちょう Usage 8%
Traditional spelling using 脹. Still seen in older texts or formal contexts, but 膨張 is now dominant.
Kanji 張 counter for bows & stringed instruments, stretch, spread Similar words 拡かく 大だい 拡大 is more about enlargement or magnification (scale, scope), while 膨張 emphasizes swelling or bloating, often with a nuance of internal pressure or uncontrolled growth.
収しゅう 縮しゅく 収縮 is the antonym, meaning contraction or shrinkage.
Etymology Compound of 膨 (ふくらむ, 'to swell') and 張 (はる, 'to stretch'). The alternative kanji 脹 also means 'to swell', making 膨脹 a synonymous compound.
