How to say "insufficient" in Japanese

• 少ないすくないJLPT N5approx.Common
  i-adjectiveCovers insufficient in the sense of a small amount or number: few, little, or low. It describes quantity itself, as in funds or information being scarce, rather than quality falling short of a requirement.
  この病気びょうきに勝かてる人ひとは少すくない。↗

  Not many survive this disease.
• 不十分ふじゅうぶんCommon
  na-adjective, nounThe default translation for insufficient or inadequate: something does not fully meet a need or standard. Fits explanations, preparation, evidence, or time that is lacking or imperfect in some way.
  これらの２つの分子ぶんしが異ことなったスピードで動うごいていることを示しめすだけでは不十分ふじゅうぶんである。↗

  It is not enough to show that these two particles are moving at different speeds.
• 過少かしょうCommon
  na-adjectiveMeans too few or too little — insufficient by being below a proper amount. Often used in formal or written contexts such as reports and statistics when a figure, payment, or estimate falls short of what it should be.
• 悪いわるいJLPT N5approx.Common
  i-adjectivePrimarily means bad or poor, and only touches insufficient through the sense of poor quality or inferior condition. For example health or eyesight being bad. Seldom the word you want for insufficiency of amount; choose another entry for that.
  私のステレオはあなたのより音質おんしつが悪わるい。↗

  My stereo set is inferior to yours in sound quality.
• 手薄てうすCommon
  na-adjective, nounSpecifically describes supplies being short or stocks, money, or staff running thin. Use it when resources available are insufficient for demand, as in inventory or funding being in short supply.

Use 不十分 for the general sense of insufficient or inadequate, 「少ない」 for small amounts, 過少 for too few or too little, 手薄 for short supplies such as stock or money, and 「悪い」 only for poor quality.

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

• 少ないすくないfew
• 不十分ふじゅうぶんinsufficient
• 過少かしょうtoo few
• 額が少ないがくがすくないinsufficient (money, etc.)
• 足りないたりないinsufficient
• 足らないたらないinsufficient
• 悪いわるいpoor (quality)
• 手薄てうすinsufficient (stock, money, etc.)
• 足らずたらずinsufficient
• 仕方ないしかたないit's no use (doing)
• 仕方がないしかたがないit's no use (doing)
• しょうがないit's no use (doing)
• 仕方のないしかたのないpointless
• 致し方ないいたしかたないit's no use (doing)
• 甘いあまいinsufficient
• 生なまinsufficient