a soft material used for making mattresses (= the soft part of a bed that you lie on), etc. that changes shape to fit the shape of your body

I invested in a memory foam mattress and I have never slept so well. 我花大钱买了一个记忆海绵床垫，睡眠从来没有这么好过。

Among the most popular of these pillows are those made from memory foam. 这些枕头中最受欢迎的是记忆泡沫做的枕头。