noun /ɪkˈskɜːsəs/
a) A fuller treatment (in a separate section) of a particular part of the text of a book, especially a classic.

Here is what us scholars call an excursus. If you are an honest man the following page or two can be of no possible interest to you.

b) A narrative digression, especially to discuss a particular issue.

In his excursus on the Jewish people at the opening of the fifth book of his Histories [...], Tacitus was at a loss to uncover any deep cause for the war that broke out in 66.

See Also: excursion

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