Kalyn, walkabout123, thank you very much!

I've never heard of either, but here are the definitions I found on the internet (I copied and pasted them directly from Bing): Sponge bag - a waterproof bag for holding bathrooms items (soap and toothpaste etc.) when you are travelling. toilet bag. bag - a flexible container with a single opening; "he stuffed his laundry into a large bag". A wash bag is a small mesh bag that protects delicate clothes in the washer. To use a wash bag, fill it with your desired articles, seal it shut and toss it into the washer. Hope that helps!

They mean the same thing. They are small bags that you put in your suitcase when traveling. This includes things like toothpaste, toothbrush, deodorant, etc. In the U.S. we call them toiletry bags, or we put such items in a cosmetic bag. A wash bag also refers to a portable bag you use for washing small clothing items when you go camping.