かくべからざる

かくべからざる【欠く可からざる】

indispensable; not to be dispensed with; essential; of the essence; requisite 《to…》.

●欠くべからざるもの a requisite; an essential; a necessity; the necessaries

・音楽は私の生活にとって欠くべからざるものだ. Music is indispensable in [to] my life. | Music is something I could not do without in my life.

・岩壁登攀(_とうはん)に必要欠くべからざる装備 the (absolutely) essential equipment for rock-climbing.

●一人一人がチームにとって欠くべからざる存在である. Each and every member is indispensable to the team.