How to say "deficiency" in Japanese
Choosing the right word
- 不足ふそくnoun, suru verb, intransitive verb, na-adjectiveThe word for a shortage or insufficiency of something needed — sleep, money, time, nutrients. When 'deficiency' simply means 'not enough' of something, this is typically the word you want.
- 欠乏けつぼうnoun, suru verb, intransitive verbA weightier word for an outright lack or want of something essential — nutrients, resources, and other necessities — implying deprivation rather than a mere shortfall in quantity.
- 不備ふびna-adjective, no-adjectiveCovers 'deficiency' as a defect or inadequacy in an arrangement, plan, system, or document — something incomplete or not properly in place. It does not refer to shortages of quantities or supplies.
- 欠けつnounSeldom the word you want for 'deficiency': it is really a component found inside other words rather than an independent term, so do not reach for it to express a lack.
- 欠陥けっかんnounMatches 'deficiency' only in the sense of a defect or flaw inherent in a product, structure, or design — a fault in the thing itself, not a shortage of anything.
不足 fits an ordinary shortage of something needed, 欠乏 a more severe lack of essentials, 不備 defects in arrangements or paperwork, 欠陥 flaws in products or designs, and 欠 is a component rather than an independent word.
Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only
Japanese equivalents
See also
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