I use the term list to mean two things: either a multiset or (more often) an tuple. Lists are countable collections (multisets) in some order (like a tuple). That is, it makes sense to talk about the 1st (or 7th, or nth) element of a list, and the nth and mth elements of a list can be equal, even if n ≠ m (the elements of a list need not be distinct).