aside vs excursus

aside and excursus both are nouns.

Word	Noun	Adjective	Verb	Adverb
aside	Yes	No	No	Yes
excursus	Yes	No	No	No

As nouns, aside and excursus are synonyms defined as:

Other synonyms of aside include digression, divagation, parenthesis.

aside (noun)	excursus (noun)
a line spoken by an actor to the audience but not intended for others on the stage	a message that departs from the main subject
a message that departs from the main subject

aside (adverb)	excursus (adverb)
on or to one side
out of the way (especially away from one's thoughts)
in reserve; not for immediate use
not taken into account or excluded from consideration
placed or kept separate and distinct as for a purpose
in a different direction