expression
you can't make an omelet without breaking eggs; a small sacrifice may be necessary to solve a more pressing problem
Proverb meaning that to deal with a greater problem, one must sometimes endure a lesser loss or sacrifice. Literally 'you can't replace your belly with your back' — the belly (vital) cannot be sacrificed for the back (less vital).
See also: 背に腹は替えられない
背に腹は替えられぬから、多少の出費は仕方ない。
You can't make an omelet without breaking eggs, so some expense is unavoidable.
背に腹は替えられぬというように、彼は嫌な仕事も引き受けた。
As the saying goes, a small sacrifice may be necessary; he took on the unpleasant job.
Modern colloquial form using 替えられない instead of classical 替えられぬ. Same meaning, but ぬ is more literary/proverbial.
A classical Japanese proverb using the archaic negative auxiliary ぬ. The literal meaning is 'one cannot substitute the belly with the back,' implying that vital needs (belly) take precedence over less critical ones (back).