不十分・不充分|ふじゅうぶんfujuubun[2]nakadaka (mid-high)

1. na-adjective, nouninsufficient; inadequate; imperfect
   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.

• Synonym不足ふそくNeutralCovers shortage in quantity or degree, as in 「人手不足」「説明不足」; mostly used in compounds, while 「不十分」 usually stands alone.
• Synonym不備ふびWrittenWritten/formal: procedures or equipment that are incomplete or have gaps, as in 「書類の不備」; 「不十分」 is about degree falling short.
• Synonym不完全ふかんぜんNeutralMeans something is incomplete, with parts missing or faulty; 「不十分」 says it is not sufficiently thorough.
• Synonym不全ふぜんWrittenWritten/formal: a state or function is not fully working, as in 「心不全」「機能不全」; also used for organizations and systems beyond medicine.
• Synonym物足りないものたりないNeutralExpresses a sense that something is missing or not quite satisfying; 「不十分」 is an objective judgement of falling short of requirements.
• Synonym欠けつWrittenA single written/formal character for lack or absence, as in 「欠員」; not used on its own in everyday speech.
• Synonym足りないたりないNeutralColloquial and very widely used for there not being enough; 「不十分」 leans written and evaluates degree or quality.
• Related貧しいまずしいNeutralMeans poor or needy, and figuratively meagre in content; 「不十分」 never implies poverty.
• Related貧弱ひんじゃくNeutralSuggests something frail, thin or shabby, as in 「貧弱な体」; 「不十分」 only says something is insufficient.
• Related手薄てうすNeutralUsed for being short of staff or reserves, as in 「警備が手薄」; 「不十分」 covers a much broader range.
• Related乏しいとぼしいWrittenWritten/formal: scarce or lacking, as in 「経験に乏しい」; 「不十分」 is a judgement that something is not adequate enough.
• Related希薄きはくWrittenWritten/formal: thin or faint, as in 「関心が希薄」; 「不十分」 means the degree or amount is not enough.
• Related欠乏けつぼうWrittenWritten/formal: a necessary thing is in short supply, material or emotional, as in 「ビタミン欠乏」「愛情の欠乏」; 「不十分」 evaluates degree.
• Related欠如けつじょWrittenWritten/formal: a quality or element is absent, as in 「責任感の欠如」; 「不十分」 judges something as failing to meet the required level.
• Antonym十分じゅうぶんNeutralMeans enough or sufficient; the direct opposite of 「不十分」.

Use 「不十分」 when something is not thorough or adequate enough. For plain shortage, 「不足」 and 「足りない」 also work. Pick 「不備」 for incomplete procedures or equipment, 「欠如」 for a missing quality, and 「物足りない」 when something feels somehow lacking or unsatisfying.

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

1. 不足ふそくしているところがあり満足まんぞくできないこと。また、その様よう。