Decline or ruin; the falling into disrepute or loss of status/wealth (of a family, business, power, etc.).
かつての名門家は一代で没落してしまった。
The once-distinguished family fell into ruin within a single generation.
不祥事が原因で会社が没落したと報じられた。
It was reported that the company fell into decline due to a scandal.
戦後、旧勢力の多くが没落した。
After the war, many of the old powers declined.