> so why accept single character name?

Because readability suffers with repeated long variable names

There's a reason why math uses i,j,k and x,y,z and it's not to be petty.

There's also a reason why a lot of people find equations incredibly hard to parse.

This is a nice semi-random deeply nested spot to observe how the topic of naming is so cognitively attractive.

Even in the meta-sense it is being discussed here.

There is something about naming that we like thinking about, and fine tune our thoughts on, more than a simple need for legibility.

There is a sense of ownership in picking a name.

Are you awful or just trolling? I've said that naming is very important, but I didnt't suggest that people should choose a longer word when two are equivalent. A real way to give 'more meaning' to the index is to indicate to which collection it belongs.