How to say "vital" in Japanese

• 肝要かんようCommon
  na-adjective, nounThe 'vital = essential, crucial' sense: it states plainly that something is extremely important and must not be neglected. Typical in statements about what a plan or undertaking depends on.
  危機ききの際さいにも冷静れいせいさを失うしなわず、狂気きょうきに走はしるのを避さけることが肝要かんようである。↗

  It is essential to keep calm in a time of crisis and avoid going haywire.
• 元気げんきJLPT N5approx.Common
  na-adjective, nounNot the 'crucially important' sense: 元気 is the 'vital' of being full of life — a lively, spirited, healthy, energetic person. For 'vital' meaning essential, it is seldom what you want.
• 肝心かんじんJLPT N1approx.Common
  na-adjective, no-adjectiveAlso the 'crucially important' sense, with the nuance of the point that really matters — the thing everything else hinges on. It largely overlaps with 肝要, and either is a natural choice for 'vital'.
  なんであれ物事ものごとの本体ほんたいを捕とらえる事ことが肝心かんじんだ。↗

  No matter what the problem is, it's essential to get at the heart of the matter.
• 緊要きんようCommon
  na-adjective, nounCovers 'vital' through its urgent, momentous side: matters of pressing importance that demand attention. For the plain 'crucially important' sense, 肝心 or 肝要 is normally the better choice.

For 'vital' meaning crucially important, choose 肝心 or 肝要; 元気 only covers the 'full of life and energy' sense, and 緊要 leans toward urgent, momentous matters.

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

• 肝要かんようextremely important
• 元気げんきlively
• 肝心かんじんessential
• 緊要きんようmomentous
• バイタルvital
• 切要せつようessential
• 必要不可欠ひつようふかけつabsolutely essential
• 欠かせないかかせないindispensable
• 核心的かくしんてきcrucial