ex·cur·sion (k-skûrzhn)
n.
1. A usually short journey made for pleasure; an outing.
2. A roundtrip on a passenger vehicle at a special low fare.
3. A group taking a short pleasure trip together.
4. A diversion or deviation from a main topic; a digression.
5. Physics
a. A movement from and back to a mean position or axis in an oscillating or alternating motion.
b. The distance traversed in such a movement
I'd say 'excursion' was about right!
