Нашёл. В Википедии, по ссылке [1], написано следующее
The name persists even though standard notation has changed, since the use of a comma as an operator is potentially confusing, and even Lawvere dislikes the uninformative term "comma category" (Lawvere, 1963 p. 13).
и дана ссылка на страницу 13 текста [2], то есть на комментарии автора к оригинальной диссертации.
Собственно, цитата:
The \((\phantom{x}, \phantom{x})\) operation then turned out to be fundamental in computing Kan extensions (i.e. adjoints of induced functors). Unfortunately, I did not suggest a name for the operation, so due to the need for reading it somehow or other, it rather distressingly came to be known by the subjective name ``comma category'', even when it came to be also denoted by a vertical arrow in place of the comma. Originally, it had been common to write \((A, B)\) for the set of maps in a given category \(\mathcal{C}\) from an object \(A\) to an object \(B\); since objects are just functors from the category \(1\) to \(\mathcal{C}\), the notation was extended to the case where \(A\) and \(B\) are arbitrary functors whose domain categories are not necessarily \(1\) and may also be different.
Жесть, как я мог это пропустить, я же открывал Википедию! Всем спасибо, простите за беспокойство.
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