膨らます|ふくらますfukuramasu[0]heiban (flat)

JLPT N2approx.Common
Definitions
  1. godan verb, transitive verbto swell; to expand; to inflate; to bulge
    Yeast makes dough rise.
Conjugation
Dictionary form膨らます(ふくらます)
Polite (masu)膨らまします(ふくらまします)
Negative (nai)膨らまさない(ふくらまさない)
polite (masen)膨らましません(ふくらましません)
classical zu / nu膨らまさず・膨らまさぬ(ふくらまさず・ふくらまさぬ)
Past (ta)膨らました(ふくらました)
polite (mashita)膨らましました(ふくらましました)
Past negative (nakatta)膨らまさなかった(ふくらまさなかった)
polite (masen deshita)膨らましませんでした(ふくらましませんでした)
Te form膨らまして(ふくらまして)
Potential膨らませる(ふくらませる)
Passive膨らまされる(ふくらまされる)
Causative膨らまさせる(ふくらまさせる)
Causative passive膨らまさせられる(ふくらまさせられる)
Conditional (ba)膨らませば(ふくらませば)
tara膨らましたら(ふくらましたら)
Volitional膨らまそう(ふくらまそう)
polite (mashou)膨らましましょう(ふくらましましょう)
Imperative膨らませ(ふくらませ)

Common forms generated by rule; see the senses for honorific or irregular usage.

Transitive / intransitive pair
transitive膨らますふくらます⇄intransitive膨らむふくらむ
風船ふうせんを膨ふくらます
膨らむ describes a balloon expanding on its own; 膨らます means to cause that expansion, as when someone inflates a balloon.
transitive膨らますふくらます⇄intransitive膨れるふくれる
パンを膨ふくらます
膨れる expresses bread swelling by itself, as dough rises; 膨らます expresses making it swell, as a baker does.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

Synonyms & antonyms
  • Synonym膨らせるふくらせるNeutralSame meaning as 「膨らます」: to puff up or inflate something. The two words are interchangeable.
  • Synonym膨らすふくらすCasualA colloquial variant of 「膨らます」 with the same sense of inflating or expanding something; used less often.
  • Antonym縮めるちぢめるNeutralThe opposite of 「膨らます」: to shorten or reduce something, as in 「距離を縮める」.
  • Antonym萎ませるNeutralTo make something go limp or wither — the reverse of puffing something up with 「膨らます」.

Use 「膨らます」 for inflating a balloon, puffing out your cheeks, or expanding a dream; 「膨らせる」 is an interchangeable equivalent and 「膨らす」 a less common colloquial variant. For the opposite, 「縮める」 shrinks or shortens, and 「萎ませる」 deflates or wilts.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

Japanese definitions
  1. 膨ふくらむようにする。膨ふくらませる。
Kanji in this word
English equivalents
See also

JLPT vocabulary levels are community estimates, not official (no official lists have been published since the 2010 revision).

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