a wandering from a subject; digression.
2. excursion ·- a running or going out or forth; an expedition; a sally.
3. excursion ·- length of stroke, as of a piston; stroke. [an awkward use of the word.].
4. excursion ·- a journey chiefly for recreation; a pleasure trip; a brief tour; as, an excursion into the country.