excursus
UK[ɪkˈskɜːsəs]US[ɪkˈskɜːrsəs]
n
A detailed discussion of a particular point in a book, usually in an appendix or a footnote.
n
A digression or an incidental excursion into a related topic.
Morpheme Breakdown
ex
curs
us
ex
out
curs
run
us
noun suffix
Etymology
The word 'excursus' is a direct borrowing from Latin, where it literally meant "a running out" or "a digression." It is built upon the past participle stem of the verb excurrere, which combines ex- ("out") and currere ("to run"). The core semantic logic is metaphorical: just as one might physically run out from a main path, an excursus represents a literary or discursive "running out" from the main narrative or argument. This Latin term was adopted into scholarly English in the early 19th century to formally denote a lengthy, appended discussion that diverges from the principal text.
Analysis
Structure: ex (out) + curs (run) + us (noun suffix)
- ex: Latin origin, a prefix meaning "out of, from, thoroughly."
- curs: Latin origin, from the root of currere meaning "to run."
- us: Latin origin, a masculine noun suffix indicating an action, process, or result.
Examples
The book includes a lengthy excursus on the historical context of the legal code.
His lecture was full of fascinating excursuses into tangential philosophical debates.
The author placed the technical proofs in an excursus at the end of the chapter to avoid disrupting the main flow.