excursion
noun
ex·cur·sion
| \ ik-ˈskər-zhən
\
\
Definition of excursion
1a
: a going out or forth : expedition
b(1)
: a usually brief pleasure trip
(2)
: a trip at special reduced rates
2
: deviation from a direct, definite, or proper course
especially
: digression
needless excursions into abstruse theory
3
: a movement outward and back or from a mean position or axis
also
: the distance traversed : amplitude
the excursion of a piston