D defs.my
Entry 1 sense Webster, 1913

Excursus

· Ex·cur·sus · IPA /ɛkˈskɝsəs/
01 n. A dissertation or digression appended to a work, and containing a more extended exposition of some important point or topic.
  1. 1.
    A dissertation or digression appended to a work, and containing a more extended exposition of some important point or topic.