Possible Definitions:
1. Excursion () A running or going out or forth; an expedition; a sally.
2. Excursion () A journey chiefly for recreation; a pleasure trip; a brief tour; as, an excursion into the country.
3. Excursion () A wandering from a subject; digression.
4. Excursion () Length of stroke, as of a piston; stroke. [An awkward use of the word.]