a small waterproof bag used for carrying your toothbrush, facecloth, soap, etc. when you are travelling

I travel a lot so I have a ready-packed washbag and just put it in the bag. 我经常旅行，所以我有一个收拾好的洗漱包，放在包里就可以出门。

The little soaps, etc. you get from hotels are good for putting in your wash bag when you go away. 酒店送的小香皂之类的东西很适合出门的时候放在洗漱包里。