Use of こと in this dictionary entry

Question

I was looking up the word "出席" (attendance) in a Japanese dictionary, and found the following definition:

学校の授業や会合などに出ること。

From my understanding, I assume こと is added as a normalizer is so that "出る (to turn up/ to appear)" becomes a noun "出ること (the thing of turning up/showing up)". Hence, the definition means "The thing about turning up for the school's class or meeting".

My question is if this is done so that "the thing of showing up" which derives from adding こと to 出る to change the verb into a noun is so that "the thing" refers to the word, which I assume to be a noun, "出席".

So the sentence becomes something like "Attendance(The thing = Attendance) is about turning up/ being present for the school's class or meeting". This is a poor intepretation but this is for the sake of expressing what I meant in my question.

Answer 1

This works just like any English dictionary would. My dictionary gives the really helpful definition:

Attendance: the act of attending.

The こと in your definition simply corresponds to 'act', and so is a nominaliser, as you say. The whole phrase Xこと is then 'the act of doing X'.