Akademik

excursion
n.
1 a short journey or ramble for pleasure, with return to the starting-point.
2 a digression.
3 Astron. a deviation from a regular path.
4 archaic a sortie (see ALARUM).
Derivatives:
excursional adj. excursionary adj. excursionist n.
Etymology: L excursio f. excurrere excurs- (as EX-(1), currere run)

Useful english dictionary. 2012.