Pipeclay
（造烟管或皮革用的）白黏土, <喻>（军队对服装等的）严格要求
📖 牛津释义
pipeclay
n [U] fine white clay used (esp formerly) for making tobacco pipes and for whitening leather, etc 白陶土（尤於旧时用以制烟斗、 使皮革增白等）.
🗣️ 情景例句
I shouldn't have done that.
我不该那么做。
My underwear is black.
我的内衣是黑色的。
And what's this?
那么这个呢？