不ふ可か欠けつ

ふ

か

け

つ

Common wordJLPTN2Freq.FrequencyTop 10,000

Meanings

Used for something that is absolutely necessary and cannot be done without. Often appears in formal, business, or academic contexts.

〈事こと〉に不ふ可か欠けつな〈物もの〉something indispensable for X
この仕し事ごとには正せい確かくさが不ふ可か欠けつな能のう力りょくだ。
Accuracy is an indispensable skill for this job.
〈物もの〉は〈事こと〉に不ふ可か欠けつであるX is essential/indispensable for Y
水みずは生せい命めいの維い持じに不ふ可か欠けつである。
Water is essential for sustaining life.
不ふ可か欠けつな条じょう件けんindispensable condition
信しん頼らい関かん係けいは交こう渉しょうの成せい功こうに不ふ可か欠けつな条じょう件けんだ。
A relationship of trust is an indispensable condition for successful negotiation.

必ひつ要ようN4
必要 is the common, everyday word for 'necessary', while 不可欠 is stronger and more formal, emphasizing that something absolutely cannot be omitted.
必ひっ須すN1
必須 describes a mandatory requirement or prerequisite, whereas 不可欠 stresses that a thing is irreplaceable and cannot be done without.
肝かん要よう
肝要 means 'of vital importance' with a slightly literary tone, while 不可欠 specifically means 'cannot be dispensed with'.
なくてはならない
不可欠 is a formal, written Sino-Japanese adjective for 'indispensable', while 無くてはならない is a more colloquial, everyday phrase with the same meaning.
マスト
不可欠 stresses that something is indispensable in a somewhat formal register, while マスト is a light, casual way to say the same thing.

不ふ要ようN1
不要 means 'unnecessary' or 'not needed', the direct opposite of 不可欠's 'indispensable'.

不ふ可か能のうN3
不可能 (impossible) and 不可欠 (indispensable) share the 不可 prefix but describe unrelated concepts—one is about feasibility, the other about necessity.
不ふ可か解かいN1
不可欠 shares the 不可 prefix with 不可解 but means 'indispensable', a completely unrelated meaning to 不可解's 'incomprehensible'.
不ふ可か分ぶん
不可分 means 'indivisible/inseparable' (cannot be split apart), while 不可欠 means 'indispensable/essential' (cannot be done without); learners often confuse them because both start with 不可.
不ふ可か侵しん
不可欠 means 'indispensable' while 不可侵 means 'inviolable'; the shared 不可 prefix makes them easy to mix up despite very different meanings.

Compound of 不 (not) + 可欠 (possible to lack). The kanji 欠 means 'lack' or 'be missing', so 不可欠 literally means 'cannot be lacking'.