Food or goods going bad, and the loss that causes. It is a formal, business word — you meet it in shops, farms, factories, shipping, and food-safety rules, not in a home kitchen.

Food or goods going bad食物或貨品變壞, and the loss that causes以及因此造成的損失。It is a formal, business word這是一個正式的商業用字 — you meet it in shops, farms, factories, shipping, and food-safety rules你會在商店、農場、工廠、航運業，還有食品安全規定裡遇到它, not in a home kitchen而不是在家裡的廚房。

A supermarket manager talks about reducing spoilage; nobody says 'there is spoilage in my fridge.' It covers both the process (milk turning sour, fruit rotting) and the amount lost because of it, which is why you can say 'spoilage was five percent last month.' It is uncountable, so no a and no plural.

A supermarket manager talks about reducing spoilage超市經理會談到要減少spoilage， nobody says 'there is spoilage in my fridge.'沒有人會說「我冰箱裡有spoilage」。It covers both the process (milk turning sour, fruit rotting)它同時涵蓋變壞的過程（像牛奶變酸、水果腐爛）， and the amount lost because of it以及因此損失掉的量， which is why you can say 'spoilage was five percent last month.'所以你可以說「上個月的spoilage是百分之五」。It is uncountable它是不可數名詞， so no a and no plural所以不加a、也沒有複數。

Beyond food, printers and manufacturers use it for materials ruined during production.

Beyond food除了食品之外， printers and manufacturers use it for materials ruined during production印刷業和製造業也用這個字指生產過程中報廢的材料。

The everyday way to say the same thing is much simpler: the food went off, or the food went bad.

The everyday way to say the same thing is much simpler日常講法簡單多了： the food went off食物壞掉了, or the food went bad或者the food went bad。