Yeah, it is, essentially. But then, if you call a slice of toast between two slices of "bread" a sandwich, I can imagine how you would think that mayonnaise is

Yeah, it is, essentially. But then, if you call a slice of toast between two slices of "bread" a sandwich, I can imagine how you would think that mayonnaise is something that should be put on a salad. ;) Local view: The sort of bread I've seen people abroad use for toast sandwich, is essentially what we call "toast" in Germany too. Specifically, "toast", in Germany, refers to mostly pre-cut, soft bread with a squarish cross section so bland in taste and so deprived of nutrient content that only toasting will turn it into "food". Nutrient content is just as absent, after toasting, but at least the burned parts help digestion. :] So here, a toast sandwich is a slice of (toasted) bread between two untoasted slices of the same bread, more or less. I've never seen any native eat sth. like this, in Germany. On the other hand, we do have gustatorially misguided contemporaries here, too, that do think that mayonnaise-derived stuff belongs on a salad.