I usually just refer to row and column. They may not be 100% ISO approved terms, but, everyone knows what you're referring to for the most part. And if we're explaining things, the most important goal of the explanation is clarity. So we could use tuple and element to explain stuff, but then we have to go back and explain tuple and element and, at least to my mind, there's no additional clarity added by using tuple and element. Frankly, that would be an indication of a wish to be pedantic rather than a wish to help people out.